Aromatic amine derivatives and organic electroluminescent device using same

ABSTRACT

The present invention provides a novel aromatic amine derivative having a specific structure and an organic electroluminescence device in which an organic thin film layer comprising a single layer or plural layers including at least a light emitting layer is interposed between a cathode and an anode, wherein at least one layer in the above organic thin film layer, particularly a hole injecting layer contains the aromatic amine derivative described above in the form of a single component or a mixed component. Use of the aromatic amine derivative described above materialize an organic electroluminescence device which reduces an operating voltage and makes molecules less liable to be crystallized and which enhances a yield in producing the organic EL device and has a long lifetime.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. Ser. No.11/844,050, filed Aug. 23, 2007, the text of which is incorporated byreference, and claims priority to the Japanese Patent Application No.2006-226121, filed Aug. 23, 2006, the text of which is also incorporatedby reference.

BACKGROUND OF THE INVENTION

The present invention relates to an aromatic amine derivative and anorganic electroluminescence (EL) device using the same, specifically toan aromatic amine derivative which reduces the operating voltage andinhibits the molecules from being crystallized by using an aromaticamine derivative having a specific substituent for a hole transportingmaterial and which enhances a yield in producing an organic EL deviceand improves a lifetime of the organic EL device.

RELATED ART

An organic EL device is a spontaneous light emitting device making useof the principle that a fluorescent substance emits light byrecombination energy of holes injected from an anode and electronsinjected from a cathode by applying an electric field. Since an organicEL device of a laminate type driven at a low voltage was reported by C.W. Tang et al. of Eastman Kodak Company (C. W. Tang and S. A. Vanslyke,Applied Physics Letters, Vol. 51, p. 913, 1987 and the like), researcheson organic EL devices comprising organic materials as structuralmaterials have actively been carried out. Tang et al. usetris(8-quinolinolate)aluminum for the light emitting layer and atriphenyldiamine derivative for the hole transporting layer. Theadvantages of the laminate structure include an elevation in anefficiency of injecting holes into a light emitting layer, a rise in aproduction efficiency of excitons produced by blocking electronsinjected from a cathode to recombine them and shutting up of excitonsproduced in a light emitting layer. As shown in the above example, atwo-layer type comprising a hole transporting (injecting) layer and anelectron transporting and light emitting layer and a three-layer typecomprising a hole transporting (injecting) layer, a light emitting layerand an electron transporting (injecting) layer are well known as thedevice structures of an organic EL device. In such laminate typestructural devices, device structures and forming methods are studied inorder to enhance a recombination efficiency of holes and electronsinjected.

Usually, when an organic EL device is operated or stored under hightemperature environment, brought about are adverse effects such as achange in a color of emitted light, a reduction in a current efficiency,a rise in an operating voltage and a reduction in an emission lifetime.A glass transition temperature (Tg) of a hole transporting material hasto be raised in order to prevent the above matters. Accordingly, thehole transporting material has to have a lot of aromatic groups in amolecule (for example, aromatic diamine derivatives described in PatentDocument 1 and aromatic fused ring diamine derivatives described inPatent Document 2), and usually structures having 8 to 12 benzene ringsare preferably used.

However, if they have a lot of aromatic groups in a molecule,crystallization is liable to be caused in forming a thin film using theabove hole transporting materials to produce an organic EL device, andthe problems that an outlet of a crucible used for vapor deposition isclogged and that defects of a thin film originating in crystallizationare caused to bring about a reduction in a yield of an organic EL devicehave been brought about. Further, compounds having more aromatic groupsin a molecule have usually a higher glass transition temperature (Tg)but have a higher sublimation temperature, and it is considered that thephenomena that decomposition is caused in vapor deposition and that adeposited film is unevenly formed are brought about, so that the problemthat the lifetime is short has been involved therein.

On the other hand, a publicly known document in which asymmetricaromatic amine derivatives are disclosed is available. For example,aromatic amine derivatives having an asymmetric structure are describedin Patent Document 3, but no specific examples are found therein, andthe characteristics of the asymmetric compounds are not describedtherein at all. Further, the examples of asymmetric aromatic aminederivatives having phenanthrene are described in Patent Document 4, butthey are handled on the same basis as symmetric compounds, and thecharacteristics of the asymmetric compounds are not described therein atall. Also, a specific synthetic process is necessary for the asymmetriccompounds, but descriptions on the production processes of theasymmetric compounds are not clearly shown in the above patents.Further, a production process of aromatic amine derivatives having anasymmetric structure is described in Patent Document 5, but thecharacteristics of the asymmetric compounds are not described therein.Thermally stable asymmetric compounds having a high glass transitiontemperature are described in Patent Document 6, but only examples ofcompounds having carbazole are shown.

Further, amine compounds having thiophene are reported in PatentDocuments 7 to 8, but they are compounds in which diamine compounds havethiophene in a central skeleton thereof. Also, thiophene is bondeddirectly to amine in Patent Document 7. Compounds having thiophene at enend of diamine compounds are reported in Patent Documents 9 to 10, butthey are compounds in which thiophene is bonded directly to amine. Thesecompounds are unstable and hard to be refined, and therefore a puritythereof is not enhanced. When thiophene is bonded directly to amine, anelectron state of amine is varied to a large extent, and therefore thesatisfactory performances are not exhibited. On the other hand,compounds in which thiophene is bonded to amine via an aryl group aredescribed in Patent Document 11. However, these compounds assume astructure in which thiophene is not substituted to a 2-position or a3-position. A 2-position or a 3-position in thiophene has a highreactivity and is electrically unstable. Accordingly, if it is presentin a molecule, the voltage is elevated in evaluation of the device, andtherefore it is not preferred. Polymer amines are described in PatentDocument 12, but only specific examples are shown, and thecharacteristics of amine compounds in which thiophene is bonded tonitrogen via an aryl group are not described therein at all. Compoundshaving a form of polymers are described in Patent Documents 13 to 22,but they can not be vapor-deposited. Further, polar groups necessary forpolymerization reduce the performances of the device such as a lifetimeand the like, and therefore the above compounds are not preferred.

As described above, it is usually known that the compounds having athiophene structure have a high mobility, but the satisfactoryperformances are not exhibited merely by combining it with an aminestructure. Accordingly, an organic EL device having more excellentperformances has been strongly required to be developed.

Patent Document 1: U.S. Pat. No. 4,720,432

Patent Document 2: U.S. Pat. No. 5,061,569

Patent Document 3: Japanese Patent Application Laid-Open No. 48656/1996

Patent Document 4: Japanese Patent Application Laid-Open No. 135261/1999

Patent Document 5: Japanese Patent Application Laid-Open No. 171366/2003

Patent Document 6: U.S. Pat. No. 6,242,115

Patent Document 7: WO2004-058740

Patent Document 8: Japanese Patent Application Laid-Open No. 304466/1992

Patent Document 9: WO2001-053286

Patent Document 10: Japanese Patent Application Laid-Open No.287408/1995

Patent Document 11: Japanese Patent Application Laid-Open No.267972/2003

Patent Document 12: Japanese Patent Application Laid-Open No.155705/2004

Patent Document 13: Japanese Patent Application Laid-Open No.042004/2005

Patent Document 14: Japanese Patent Application Laid-Open No.259441/2005

Patent Document 15: Japanese Patent Application Laid-Open No.259442/2005

Patent Document 16: Japanese Patent Application Laid-Open No.235645/2005

Patent Document 17: Japanese Patent Application Laid-Open No.235646/2005

Patent Document 18: Japanese Patent Application Laid-Open No.082655/2005

Patent Document 19: Japanese Patent Application Laid-Open No.288531/2004

Patent Document 20: Japanese Patent Application Laid-Open No.199935/2004

Patent Document 21: Japanese Patent Application Laid-Open No.111134/2004

Patent Document 22: Japanese Patent Application Laid-Open No.313574/2002

DISCLOSURE OF THE INVENTION

The present invention has been made in order to solve the problemsdescribed above, and an object thereof is to provide an organic ELdevice which reduces an operating voltage and makes molecules lessliable to be crystallized and which is improved in a yield in producingthe organic EL device and has a long lifetime and an aromatic aminederivative which materializes the same.

Intensive researches repeated by the present inventors in order toachieve the object described above have resulted in finding that theabove object can be achieved by using a novel aromatic amine derivativehaving a specific substituent represented by the following Formula (1)as a material for an organic EL device and using it particularly for ahole transporting material, and thus the present inventors have come tocomplete the present invention.

Further, it has been found that an amino group substituted with an arylgroup having a thiophene structure represented by Formula (2) is suitedas an amine unit having the specific substituent. The above amine unithas a polar group, so that it can be interacted with an electrode, andtherefore it has the effects that charges are readily injected and thatthe operating voltage is reduced due to a high mobility since it has athiophene structure. In addition thereto, the above amine unit has asteric hindrance, so that interaction between the molecules is small,and therefore it has the effects that crystallization thereof isinhibited to enhance a yield in producing an organic EL device and thatthe organic EL device obtained is extended in a lifetime. In particular,it has been found that a marked reduction in the voltage and an effectof extending the lifetime are obtained by combining it with a blue lightemitting device. Further, in the compounds having a large molecularweight, the compounds having an asymmetric structure can be reduced in avapor deposition temperature, and therefore they can be inhibited frombeing decomposed in vapor deposition and can be extended in a lifetime.

That is, the present invention provides an aromatic amine derivativerepresented by the following Formula (1):

[wherein L₁ represents a substituted or non-substituted arylene grouphaving 6 to 50 ring atoms;at least one of Ar₁ to Ar₄ is represented by the following Formula (2):

(wherein R₁ is a substituted or non-substituted aryl group having 6 to50 ring atoms, a branched or linear alkyl group having 1 to 50 carbonatoms, a halogen atom or a cyano group;a is an integer of 1 to 3; andL₂ represents a substituted or non-substituted arylene group having 6 to50 ring carbon atoms);in Formula (1), among Ar₁ to Ar₄, the groups which are not representedby Formula (2) each are independently a substituted or non-substitutedaryl group having 6 to 50 ring atoms; provided that substituents for Ar₁to Ar₄ are an aryl group having 6 to 50 ring atoms, a branched or linearalkyl group having 1 to 50 carbon atoms, a halogen atom or a cyanogroup; provided that there is no case in which a is 2 and in which twoR₁ form a ring to be turned into a benzothiophenyl group].

Further, the present invention provides an aromatic amine derivativerepresented by any of the following Formulas (4) to (6):

[wherein L₅ to L₁₂ represent a substituted or non-substituted arylenegroup having 6 to 50 ring atoms;at least one of Ar₅ to Ar₉ is represented by Formula (7);at least one of Ar₁₀ to Ar₁₅ is represented by Formula (7);at least one of Ar₁₆ to Ar₂₁ is represented by Formula (7);

(wherein R₁ is a substituted or non-substituted aryl group having 6 to50 ring atoms, a branched or linear alkyl group having 1 to 50 carbonatoms, a halogen atom or a cyano group;a is an integer of 1 to 3; andL₂ represents a substituted or non-substituted arylene group having 6 to50 ring atoms; provided that there is no case in which a is 2 and inwhich two R₁ form a ring to be turned into a benzothiophenyl group);in Formulas (4) to (6), among Ar₅ to Ar₂₁, the groups which are notrepresented by Formula (7) each are independently a substituted ornon-substituted aryl group having 6 to 50 ring atoms; provided thatsubstituents for Ar₅ to Ar₂₁ are an aryl group having 6 to 50 ringatoms, a branched or linear alkyl group having 1 to 50 carbon atoms, ahalogen atom or a cyano group;provided that there is no case in which in Formula (5), Ar₁₁ and Ar₁₄are thienylaryl groups at the same time].

Further, the present invention provides an organic EL device in which anorganic thin layer comprising a single layer or plural layers includingat least a light emitting layer is interposed between a cathode and ananode, wherein at least one layer in the above organic thin layercontains the aromatic amine derivative described above in the form of asingle component or a mixed component.

The aromatic amine derivative of the present invention and the organicEL device obtained by using the same are reduced in an operatingvoltage, less liable to be crystallized in molecules, improved in ayield in producing the organic EL device and extended in lifetimes.

BEST MODE FOR CARRYING OUT THE INVENTION

The aromatic amine derivative of the present invention is represented bythe following Formula (1):

wherein L₁ represents a substituted or non-substituted arylene grouphaving 6 to 50 ring atoms; at least one of Ar₁ to Ar₄ is represented bythe following Formula (2):

in Formula (2), R₁ is a substituted or non-substituted aryl group having6 to 50 ring atoms, a branched or linear alkyl group having 1 to 50carbon atoms, a halogen atom or a cyano group; a is an integer of 1 to3; and L₂ represents a substituted or non-substituted arylene grouphaving 6 to 50 ring atoms.

In Formula (1), among Ar₁ to Ar₄, the groups which are not representedby Formula (2) each are independently a substituted or non-substitutedaryl group having 6 to 50 ring atoms; provided that substituents for Ar₁to Ar₄ are an aryl group having 6 to 50 ring atoms, a branched or linearalkyl group having 1 to 50 carbon atoms, a halogen atom or a cyanogroup; provided that there is no case in which a is 2 and in which twoR₁ form a ring to be turned into a benzothiophenyl group.

In the aromatic amine derivative of the present invention represented byFormula (1), Formula (2) described above is preferably represented byFormula (3) shown below;

In Formula (3), R₁ is a substituted or non-substituted aryl group having6 to 50 ring atoms or a branched or linear alkyl group having 1 to 50carbon atoms; and L₂ represents a substituted or non-substituted arylenegroup having 6 to 50 ring atoms.

In the aromatic amine derivative of the present invention, Ar₁ inFormula (1) described above is preferably represented by Formula (2)described above.

In the aromatic amine derivative of the present invention, Ar₁ and Ar₂in Formula (1) described above are preferably represented by Formula (2)described above.

In the aromatic amine derivative of the present invention, Ar₁ and Ar₃in Formula (1) described above are preferably represented by Formula (2)described above.

In the aromatic amine derivative of the present invention, three or moreof Ar₁ to Ar₄ in Formula (1) described above are preferably differentfrom each other and the molecular structure of the aromatic aminecompound is asymmetric.

In the aromatic amine derivative of the present invention, three of Ar₁to Ar₄ in Formula (1) described above are preferably the same and themolecular structure of the aromatic amine compound is asymmetric.

Preferably, in the aromatic amine derivative of the present invention,among Ar₁ to Ar₄ in Formula (1), the groups which are not represented byFormula (2) each are independently phenyl, biphenylyl, terphenylyl orfluorenyl.

In the aromatic amine derivative of the present invention, L₁ in Formula(1) described above is preferably biphenylylene, terphenylylene orfluorenylene.

In the aromatic amine derivative of the present invention, L₂ in Formula(2) described above is preferably phenylene, biphenylylene orfluorenylene.

In the aromatic amine derivative of the present invention, R₁ in Formula(2) described above is preferably phenyl, naphthyl or phenanthrene.

Preferably, in the aromatic amine derivative of the present invention,among Ar₁ to Ar₄ in Formula (1) described above, the groups which arenot represented by Formula (2) each are independently phenyl,biphenylyl, terphenylyl or fluorenyl; L₁ is biphenylylene,terphenylylene or fluorenylene; and L₂ in Formula (2) described above isphenylene, biphenylylene or fluorenylene.

Further, the aromatic amine derivative of the present invention isrepresented by any of the following Formulas (4) to (6):

in Formulas (4) to (6), L₅ to L₁₂ represent a substituted ornon-substituted arylene group having 6 to 50 ring atoms; at least one ofAr₅ to Ar₉ is represented by Formula (7); at least one of Ar₁₀ to Ar₁₅is represented by Formula (7); and at least one of Ar₁₆ to Ar₂₁ isrepresented by Formula (7).

In Formula (7), R₁ is a substituted or non-substituted aryl group having6 to 50 ring carbon atoms, a branched or linear alkyl group having 1 to50 atoms, a halogen atom or a cyano group; a is an integer of 1 to 3; L₂represents a substituted or non-substituted arylene group having 6 to 50ring atoms; provided that there is no case in which a is 2 and in whichtwo R₁ form a ring to be turned into a benzothiophenyl group.

In Formulas (4) to (6), among Ar₅ to Ar₂₁, the groups which are notrepresented by Formula (7) each are independently a substituted ornon-substituted aryl group having 6 to 50 ring atoms; provided thatsubstituents for Ar₅ to Ar₂₁ are an aryl group having 6 to 50 ringatoms, a branched or linear alkyl group having 1 to 50 carbon atoms, ahalogen atom or a cyano group;

provided that there is no case in which in Formula (5), Ar₁₁ and Ar₁₄are thienylaryl groups at the same time.

In the aromatic amine derivatives of the present invention representedby Formulas (4) to (6), Formula (7) described above is preferablyrepresented by Formula (8) shown below;

In Formula (8), R₁ is a substituted or non-substituted aryl group having6 to 50 ring atoms or a branched or linear alkyl group having 1 to 50carbon atoms; and L₂ represents a substituted or non-substituted arylenegroup having 6 to 50 ring atoms.

In the aromatic amine derivative of the present invention, at least oneof Ar₅ to Ar₉ in Formula (4) described above is preferably representedby Formula (7).

In the aromatic amine derivative of the present invention, Ar₅ inFormula (4) described above is preferably represented by Formula (7)described above.

In the aromatic amine derivative of the present invention, Ar₆ and Ar₈in Formula (4) described above are preferably represented by Formula (7)described above.

In the aromatic amine derivative of the present invention, at least oneof Ar₁₀ to Ar₁₅ in Formula (5) described above is preferably representedby Formula (7).

In the aromatic amine derivative of the present invention, Ar₁₀ and Ar₁₅in Formula (5) described above are preferably represented by Formula (7)described above.

In the aromatic amine derivative of the present invention, Ar₁₁ and Ar₁₃in Formula (5) described above are preferably represented by Formula (7)described above.

In the aromatic amine derivative of the present invention, at least oneof Ar₁₆ to Ar₂₁ in Formula (6) described above is preferably representedby Formula (7).

In the aromatic amine derivative of the present invention, Ar₁₆, Ar₁₈and Ar₂₀ in Formula (6) described above are preferably represented byFormula (7) described above.

In the aromatic amine derivative of the present invention, among Ar₅ toAr₂₁ in Formulas (4) to (6) described above, the groups which are notrepresented by Formula (7) are preferably phenyl, biphenylyl,terphenylyl or fluorenyl.

Preferably, in the aromatic amine derivative of the present invention,L₅ to L₁₂ in Formulas (4) to (6) described above each are independentlyphenylene, biphenylylene, terphenylylene or fluorenylene.

In the aromatic amine derivative of the present invention, L₂ in Formula(7) described above is preferably phenylene, biphenylylene orfluorenylene.

In the aromatic amine derivative of the present invention, R₁ in Formula(7) described above is preferably phenyl, naphthyl or phenanthrene.

In the aromatic amine derivative of the present invention, among Ar₅ toAr₂₁ in Formulas (4) to (6) described above, the groups which are notrepresented by Formula (7) are preferably phenyl, biphenylyl,terphenylyl or fluorenyl; L₅ to L₁₂ are preferably phenylene,biphenylylene, terphenylylene or fluorenylene; and L₂ in Formula (7) ispreferably phenylene, biphenylylene or fluorenylene.

The substituted or non-substituted aryl groups having 6 to 50 ring atomsrepresented by Ar₁ to Ar₂₁ in Formulas (1) and (4) to (6) and R₁ inFormulas (2), (3), (7) and (8) include, for example, phenyl, 1-naphthyl,2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl,2-phenanthryl, 3-phenanthryl, 4-phenanthryl, 9-phenanthryl,1-naphthacenyl, 2-naphthacenyl, 9-naphthacenyl, 1-pyrenyl, 2-pyrenyl,4-pyrenyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, p-terphenyl-4-yl,p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl,m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-t-butylphenyl,p-(2-phenylpropyl)phenyl, 3-methyl-2-naphthyl, 4-methyl-1-naphthyl,4-methyl-1-anthryl, 4′-methylbiphenylyl, 4″-t-butyl-p-terphenyl-4-yl,fluoranthenyl, fluorenyl and the like.

Among them, phenyl, naphthyl, biphenylyl, terphenylyl and fluorenyl arepreferred.

In a thiophene compound, a 2-position or a 3-position has a highreactivity, and therefore these substitution positions are preferablyprotected. A publicly known document includes Macromol. Rapid Commun.,2001, 22, p. 266 to 270, and it is reported therein that they areelectrically unstable and allow polymerization to proceed. Thesubstituent is preferably an alkyl group or an aryl group, and it ispreferably an aryl group, more preferably a non-substituted aryl groupfrom the viewpoint of a stability of the compound.

The substituted or non-substituted arylene groups having 6 to 50 ringatoms represented by L₁ and L₅ to L₁₂ in Formulas (1) and (4) to (6) andL₂ in Formulas (2), (3), (7) and (8) include groups obtained byconverting the examples of the aryl group described above into divalentgroups.

The substituted or non-substituted alkyl groups having 1 to 50 carbonatoms represented by R₁ in Formulas (2), (3), (7) and (8) include, forexample, methyl, ethyl, propyl, isopropyl, n-butyl, s-butyl, isobutyl,t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, chloromethyl,1-chloroethyl, 2-chloroethyl, 2-chloroisobutyl, 1,2-dichloroethyl,1,3-dichloroisopropyl, 2,3-dichloro-t-butyl, 1,2,3-trichloropropyl,bromomethyl, 1-bromoethyl, 2-bromoethyl, 2-bromoisobutyl,1,2-dibromoethyl, 1,3-dibromoisopropyl, 2,3-dibromo-t-butyl,1,2,3-tribromopropyl, iodomethyl, 1-iodoethyl, 2-iodoethyl,2-iodoisobutyl, 1,2-diiodoethyl, 1,3-diiodoisopropyl,2,3-diiodo-t-butyl, 1,2,3-triiodopropyl, cyanomethyl, 1-cyanoethyl,2-cyanoethyl, 2-cyanoisobutyl, 1,2-dicyanoethyl, 1,3-dicyanoisopropyl,2,3-dicyano-t-butyl, 1,2,3-tricyanopropyl, trifluoromethyl, cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 1-adamantyl,2-adamantyl, 1-norbornyl, 2-norbornyl and the like. They are preferablya saturated linear, branched or cyclic alkyl group and include, to bespecific, methyl, ethyl, propyl, isopropyl, n-butyl, s-butyl, isobutyl,t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 1-adamantyl, 2-adamantyl,1-norbornyl, 2-norbornyl and the like.

The halogen atoms represented by R₁ in Formulas (2), (3), (7) and (8)include a fluorine atom, a chlorine atom, a bromine atom and an iodineatom.

The examples of the aryl group having 6 to 50 ring atoms, the branchedor linear alkyl group having 1 to 50 carbon atoms, the halogen atom andthe cyano group which are substituents for Ar₁ to Ar₂₁ include the samegroups as described above.

In Formulas (2) and (7), a is an integer of 1 to 3. When a is 2 or more,plural R₁ may be combined with each other to form a saturated orunsaturated cyclic structure of a five-membered ring or a six-memberedring which may be substituted. Provided that an aromatic ring isexcluded.

The above cyclic structure of a five-membered ring or a six-memberedring which may be formed includes, for example, cycloalkanes having 4 to12 carbon atoms such as cyclopentane, cyclohexane, adamantane,norbornane and the like, cycloalkenes having 4 to 12 carbon atoms suchas cyclopentene, cyclohexene and the like and cycloalkadienes having 6to 12 carbon atoms such as cyclopentadiene, cyclohexadiene and the like.

The specific examples of the aromatic amine derivatives of the presentinvention represented by Formulas (1) and (4) to (6) are shown below,but they shall not be restricted to these compounds shown as theexamples.

The aromatic amine derivative of the present invention is preferably amaterial for an organic electroluminescence device.

The aromatic amine derivative of the present invention is preferably amaterial for an organic electroluminescence device for vapor deposition.

The aromatic amine derivative of the present invention is preferably ahole transporting material for an organic electroluminescence device.

The organic EL device of the present invention is an organic EL devicein which an organic thin film layer comprising a single layer or plurallayers including at least a light emitting layer is interposed between acathode and an anode, wherein at least one layer in the above organicthin film layer contains the aromatic amine derivative described abovein the form of a single component or a mixed component.

In the organic EL device of the present invention, the above organicthin film layer comprises a hole transporting layer, and the aromaticamine derivative described above is preferably contained in the abovehole transporting layer.

In the organic EL device of the present invention, the above organicthin film layer comprises plural hole transporting layers, and thearomatic amine derivative described above is preferably contained in thelayer which is not brought into direct contact with the light emittinglayer.

In the organic EL device of the present invention, the above organicthin film layer comprises a hole injecting layer, and the aromatic aminederivative described above is preferably contained in the above holeinjecting layer. Further, the aromatic amine derivative described aboveis preferably contained in the hole injecting layer described above as amain component.

A fluorescent dopant is preferably a compound selected according to arequired light emitting color from amine base compounds, aromaticcompounds, chelate complexes such as tris(8-quinolinolato)aluminumcomplex and the like, coumarin derivatives, tetraphenylbutadienederivatives, bisstyrylarylene derivatives, oxadiazole derivatives andthe like, and in particular, it includes arylamine compounds andstyrylamine compounds. Among them, styrylamine compounds, styryldiaminecompounds, aromatic amine compounds and aromatic diamine compounds aremore preferred. Fused polycyclic aromatic compounds (excluding aminecompounds) are further preferred. The above fluorescent dopants may beused alone or in combination of a plurality thereof.

The above styrylamine compounds and styryldiamine compounds arepreferably compounds represented by the following Formula (A):

(wherein Ar³ is a group selected from phenyl, naphthyl, biphenyl,terphenyl, stilbene and distyrylaryl; Ar⁴ and Ar⁵ each are an aromatichydrocarbon group having 6 to 20 carbon atoms, and Ar³, Ar⁴ and Ar⁵ maybe substituted; p is an integer of 1 to 4, and among them, p ispreferably an integer of 1 to 2; any one of Ar³ to Ar⁵ is a groupcontaining a styryl group; and at least one of Ar⁴ and Ar⁵ is morepreferably substituted with a styryl group).

In this regard, the aromatic hydrocarbon group having 6 to 20 carbonatoms includes phenyl, naphthyl, anthracenyl, phenanthryl, terphenyl andthe like.

The aromatic amine compound and the aromatic diamine compound arepreferably compounds represented by the following Formula (B):

(wherein Ar⁵ to Ar⁸ are a substituted or non-substituted aryl grouphaving 5 to 40 ring carbon atoms; q is an integer of 1 to 4, and amongthem, q is preferably an integer of 1 to 2).

In this regard, the aryl group having 5 to 40 ring carbon atomsincludes, for example, phenyl, naphthyl, anthracenyl, phenanthryl,pyrenyl, coronyl, biphenyl, terphenyl, pyrrolyl, furanyl, thiophenyl,benzothiophenyl, oxadiazolyl, diphenylanthracenyl, indolyl, carbazolyl,pyridyl, benzoquinolyl, fluoranthenyl, acenaphthofluoranthenyl,stilbene, perylenyl, chrysenyl, picenyl, triphenylenyl, rubicenyl,benzoanthracenyl, phenylanthracenyl, bisanthracenyl or aryl groupsrepresented by the following Formulas (C) and (D), and naphthyl,anthracenyl, chrysenyl, pyrenyl and an aryl group represented by Formula(D) are preferred.

(in Formula (C), r is an integer of 1 to 3).

Preferred substituents with which the aryl group described above issubstituted include an alkyl group having 1 to 6 carbon atoms (ethyl,methyl, i-propyl, n-propyl, s-butyl, t-butyl, pentyl, hexyl,cyclopentyl, cyclohexyl and the like), an alkoxy group having 1 to 6carbon atoms (ethoxy, methoxy, i-propoxy, n-propoxy, s-butoxy, t-butoxy,pentoxy, hexyloxy, cyclopentoxy, cyclohexyloxy and the like), an arylgroup having to 40 ring carbon atoms, an amino group substituted with anaryl group having 5 to 40 ring carbon atoms, an ester group having anaryl group having 5 to 40 ring carbon atoms, an ester group having analkyl group having 1 to 6 carbon atoms, a cyano group, a nitro group, ahalogen atom and the like.

The fused polycyclic aromatic compounds (excluding amine compounds) arepreferably fused polycyclic aromatic compounds such as naphthalene,anthracene, phenanthrene, pyrene, coronene, biphenyl, terphenyl,pyrrole, furan, thiophene, benzothiophene, oxadiazole, indole,carbazole, pyridine, benzoquinoline, fluoranthene, benzofluoranthene,acenphthofluoranthene, stilbene, perylene, chrysene, picene,triphenylene, rubicene, benzoanthracene and the like and derivativesthereof.

In the aromatic amine derivative of the present invention, a layerbrought into contact with the anode among the respective layersconstituting the hole injecting layer and/or the hole transporting layereach described above is preferably a layer containing an acceptormaterial.

The acceptor is an easily reducing organic compound.

Easiness of reduction in compounds can be measured by a reductionpotential. In the present invention, compounds having a reductionpotential of −0.8 V or more which is measured using a saturated calomelelectrode (SCE) as a reference electrode are preferred, and compoundshaving a larger value than a reduction potential (about 0 V) oftetracyanoquinodimethane (TCNQ) are particularly preferred.

The easily reducing organic compound is preferably an organic compoundhaving an electron attracting substituent. To be specific, it includesquinoid derivatives, pyrazine derivatives, arylborane derivatives, imidederivatives and the like. The quinoid derivatives include quinodimethanederivatives, thiopyran dioxide derivatives, thioxanthene dioxidederivatives, quinone derivatives and the like.

The aromatic amine derivative of the present invention is usedpreferably for an organic EL device which emits light of a blue color.

The device structure of the organic EL device of the present inventionshall be explained below.

(1) Structure of the Organic EL Device

The typical examples of the device structure of the organic EL device ofthe present invention include structures such as:

-   (1) Anode/light emitting layer/cathode-   (2) Anode/hole injecting layer/light emitting layer/cathode-   (3) Anode/light emitting layer/electron injecting layer/cathode-   (4) Anode/hole injecting layer/light emitting layer/electron    injecting layer/cathode-   (5) Anode/organic semiconductor layer/light emitting layer/cathode-   (6) Anode/organic semiconductor layer/electron barrier layer/light    emitting layer/cathode-   (7) Anode/organic semiconductor layer/light emitting layer/adhesion    improving layer/cathode-   (8) Anode/hole injecting layer/hole transporting layer/light    emitting layer/electron injecting layer/cathode-   (9) Anode/acceptor containing layer/hole injecting layer/hole    transporting layer/light emitting layer/electron transporting    layer/electron injecting layer/cathode-   (10) Anode/insulating layer/light emitting layer/insulating    layer/cathode-   (11) Anode/inorganic semiconductor layer/insulating layer/light    emitting layer/insulating layer/cathode-   (12) Anode/organic semiconductor layer/insulating layer/light    emitting layer/insulating layer/cathode-   (13) Anode/insulating layer/hole injecting layer/hole transporting    layer/light emitting layer/insulating layer/cathode-   (14) Anode/insulating layer/hole injecting layer/hole transporting    layer/light emitting layer/electron injecting layer/cathode

Among them, usually the structure of (8) is preferably used, but itshall not be restricted to them.

The aromatic amine derivative of the present invention may be used inany organic thin film layers of the organic EL device and can be used inthe light emitting zone or the hole transporting zone, and it is usedpreferably in the hole transporting zone, particularly preferably in thehole injecting layer, whereby the molecules are less liable to becrystallized, and a yield in producing the organic EL device isenhanced.

An amount of the aromatic amine derivative of the present inventionadded to the organic thin film layer is preferably 30 to 100 mole %.

(2) Light Transmitting Substrate

The organic EL device of the present invention is prepared on a lighttransmitting substrate. The light transmitting substrate referred to inthis case is a substrate for supporting the organic EL device, and it ispreferably a flat substrate in which light in a visible region of 400 to700 nm has a light transmittance of 50% or more.

To be specific, it includes a glass plate, a polymer plate and the like.In particular, the glass plate includes soda lime glass,barium-strontium-containing glass, lead glass, aluminosilicate glass,borosilicate glass, barium borosilicate glass, quartz and the like. Thepolymer plate includes polycarbonate, acryl, polyethylene terephthalate,polyether sulfide, polysulfone and the like.

(3) Anode

An anode in the organic EL device of the present invention has afunction to inject a hole into the hole transporting layer or the lightemitting layer, and it is effective that the anode has a work functionof 4.5 eV or more. The specific examples of a material for the anodeused in the present invention include indium tin oxide alloy (ITO), tinoxide (NESA), indium-zinc oxide (IZO), gold, silver, platinum, copperand the like.

The anode can be prepared by forming a thin film from the aboveelectrode substances by a method such as a vapor deposition method, asputtering method and the like.

When light emitted from the light emitting layer is taken out from theanode, a light transmittance of the anode based on light emitted ispreferably larger than 10%. The anode has a sheet resistance ofpreferably several hundred Ω/□ or less. m A film thickness of the anodeis selected, though depending on the material, in a range of usually 10nm to 1 μm, preferably 10 to 200 nm.

(4) Light Emitting Layer

The light emitting layer in the organic EL device has the followingfunctions of (1) to (3) in combination.

(1) Injecting function: a function in which a hole can be injected froman anode or a hole injecting layer in applying an electric field and inwhich an electron can be injected from a cathode or an electroninjecting layer.

(2) Transporting function: a function in which a charge (electron andhole) injected is transferred by virtue of a force of an electric field.

(3) Light emitting function: a function in which a field forrecombination of an electron and a hole is provided and in which this isconnected to light emission.

Provided that a difference between an easiness in injection of a holeand an easiness in injection of an electron may be present and that adifference may be present in a transporting ability shown by themobilities of a hole and an electron, and any one of the charges ispreferably transferred.

A publicly known method such as, for example, a vapor deposition method,a spin coating method, an LB method and the like can be applied as amethod for forming the above light emitting layer. In particular, thelight emitting layer is preferably a molecular deposit film. In thiscase, the molecular deposit film means a thin film formed by depositinga material compound staying in a gas phase state or a film formed bysolidifying a material compound staying in a solution state or a liquidphase state, and the above molecular deposit film can usually bedistinguished from a thin film (molecular accumulation film) formed bythe LB method by a difference in an aggregation structure and a higherorder structure and a functional difference originating in it.

Further, as disclosed in Japanese Patent Application Laid-Open No.51781/1982, the light emitting layer can be formed as well by dissolvinga binding agent such as a resin and the material compound in a solventto prepare a solution and then coating the solution by a spin coatingmethod and the like to form a thin film.

When the compound of the present invention is used for the lightemitting layer, other publicly known light emitting materials excludingthe light emitting material comprising the aromatic amine derivative ofthe present invention may be added, if necessary, to the light emittinglayer as long as the object of the present invention is not damaged.Further, a light emitting layer containing a different publicly knownlight emitting material may be laminated on the light emitting layercontaining the light emitting material comprising the aromatic aminederivative of the present invention.

A light emitting material used in combination with the compound of thepresent invention is mainly an organic compound, and a doping materialwhich can be used includes, for example, anthracene, naphthalene,phenanthrene, pyrene, tetracene, coronene, chrysene, fluorescein,perylene, phthaloperylene, naphthaloperylene, perynone, phthaloperynone,naphthaloperynone, diphenylbutadiene, tetraphenylbutadiene, coumarin,oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine,cyclopentadiene, quinoline metal complexes, aminoquinoline metalcomplexes, benzoquinoline metal complexes, imine, diphenylethylene,vinylanthracene, diaminocarbazole, pyran, thiopyran, polymethine,merocyanine, imidazole chelated oxynoid compounds, quinacridone,rubrene, fluorescent coloring matters and the like. However, it shallnot be restricted to them.

The host material which can be used in combination with the compound ofthe present invention is preferably compounds represented by thefollowing Formulas (i) to (xi).

Asymmetric anthracene represented by the following Formula (i):

(wherein Ar is a substituted or non-substituted fused aromatic grouphaving 10 to 50 ring carbon atoms;Ar′ is a substituted or non-substituted aromatic group having 6 to 50ring carbon atoms;X is a substituted or non-substituted aromatic group having 6 to 50 ringcarbon atoms, a substituted or non-substituted aromatic heterocyclicgroup having 5 to 50 ring atoms, a substituted or non-substituted alkylgroup having 1 to 50 carbon atoms, a substituted or non-substitutedalkoxy group having 1 to 50 carbon atoms, a substituted ornon-substituted aralkyl group having 6 to 50 carbon atoms, a substitutedor non-substituted aryloxy group having 5 to 50 ring atoms, asubstituted or non-substituted arylthio group having 5 to 50 ring atoms,a substituted or non-substituted alkoxycarbonyl group having 1 to 50carbon atoms, a carboxyl group, a halogen atom, a cyano group, a nitrogroup or a hydroxy group;a, b and c each are an integer of 0 to 4;n is an integer of 1 to 3; and when n is 2 or more, an inside of thebrackets may be the same or different).

Asymmetric monoanthracene derivative represented by the followingFormula (ii):

(wherein Ar¹ and Ar² each are independently a substituted ornon-substituted aromatic ring group having 6 to 50 ring carbon atoms; mand n each are an integer of 1 to 4; provided that when m and n are 1and the positions of Ar¹ and Ar² bonded to the benzene ring arebilaterally symmetric, Ar¹ and Ar² are not the same, and when m and nare an integer of 2 to 4, m and n are different integers; andR¹ to R¹⁰ each are independently a hydrogen atom, a substituted ornon-substituted aromatic cyclic group having 6 to 50 ring carbon atoms,a substituted or non-substituted aromatic heterocyclic group having 5 to50 ring atoms, a substituted or non-substituted alkyl group having 1 to50 carbon atoms, a substituted or non-substituted cycloalkyl group, asubstituted or non-substituted alkoxy group having 1 to 50 carbon atoms,a substituted or non-substituted aralkyl group having 6 to 50 carbonatoms, a substituted or non-substituted aryloxy group having 5 to 50ring atoms, a substituted or non-substituted arylthio group having 5 to50 ring atoms, a substituted or non-substituted alkoxycarbonyl grouphaving 1 to 50 carbon atoms, a substituted or non-substituted silylgroup, a carboxyl group, a halogen atom, a cyano group, a nitro group ora hydroxy group).

Asymmetric pyrene derivative represented by the following Formula (iii):

[wherein Ar and Ar′ each are a substituted or non-substituted aromaticgroup having 6 to 50 ring carbon atoms;L and L′ each are a substituted or non-substituted phenylene group, asubstituted or non-substituted naphthalenylene group, a substituted ornon-substituted fluorenylene group or a substituted or non-substituteddibenzosilolylene group;m is an integer of 0 to 2; n is an integer of 1 to 4; s is an integer of0 to 2; and t is an integer of 0 to 4;L or Ar is bonded to any of 1- to 5-positions of pyrene, and L′ or Ar′is bonded to any of 6- to 10-positions of pyrene;provided that when n+t is an even number, Ar, Ar′, L and L′ satisfy (1)or (2) described below:(1) Ar≠Ar′ and/or L≠L′ (in this case, ≠ shows that both are groupshaving different structures) and(2) when Ar═Ar′ and L=L′,

(2-1) m≠s and/or n≠t or

(2-2) when m=s and n=t,

there are not a case in which (2-2-1) L and L′ or pyrene each are bondedto different bonding positions on Ar and Ar′ or (2-2-2) L and L′ orpyrene are bonded to the same bonding position on Ar and Ar′ and a casein which the substitution positions of L and L′ or Ar and Ar′ in pyreneare a 1-position and a 6-position or a 2-position and a 7-position].

Asymmetric anthracene derivative represented by the following Formula(iv):

(wherein A¹ and A² each are independently a substituted ornon-substituted fused aromatic cyclic group having 10 to 20 ring carbonatoms;Ar¹ and Ar² each are independently a hydrogen atom or a substituted ornon-substituted aromatic cyclic group having 6 to 50 ring carbon atoms;R¹ to R¹⁰ each are independently a hydrogen atom, a substituted ornon-substituted aromatic cyclic group having 6 to 50 ring carbon ringatoms, a substituted or non-substituted aromatic heterocyclic grouphaving 5 to 50 ring atoms, a substituted or non-substituted alkyl grouphaving 1 to 50 carbon atoms, a substituted or non-substituted cycloalkylgroup, a substituted or non-substituted alkoxy group having 1 to 50carbon atoms, a substituted or non-substituted aralkyl group having 6 to50 carbon atoms, a substituted or non-substituted aryloxy group having 5to 50 ring atoms, a substituted or non-substituted arylthio group having5 to 50 ring atoms, a substituted or non-substituted alkoxycarbonylgroup having 1 to 50 carbon atoms, a substituted or non-substitutedsilyl group, a carboxyl group, a halogen atom, a cyano group, a nitrogroup or a hydroxy group; Ar¹, Ar², R⁹ and R¹⁰ each may be plural, andthe adjacent groups may form a saturated or unsaturated cyclicstructure;provided that there is no case in which in Formula (1), the groupssymmetric to an X—Y axis shown on anthracene are bonded to a 9-positionand a 10-position of the above anthracene in a center).

Anthracene derivative represented by the following Formula (v):

(wherein R¹ to R¹⁰ each represent independently a hydrogen atom, analkyl group, a cycloalkyl group, an aryl group which may be substituted,an alkoxyl group, an aryloxy group, an alkylamino group, an alkenylgroup, an arylamino group or a heterocyclic group which may besubstituted; a and b each represent an integer of 1 to 5; when they are2 or more, R¹'s themselves or R²'s themselves may be the same as ordifferent from each other, and R¹'s themselves or R²'s themselves may becombined with each other to form a ring; R³ and R⁴, R⁵ and R⁶, R⁷ and R⁸and R⁹ and R¹⁰ may be combined with each other to form rings; and L¹represents a single bond, —O—, —S—, —N(R)— (R is an alkyl group or anaryl group which may be substituted), an alkylene group or an arylenegroup).

Anthracene derivative represented by the following Formula (vi):

(wherein R¹ to R²⁰ each represent independently a hydrogen atom, analkyl group, a cycloalkyl group, an aryl group, an alkoxyl group, anaryloxy group, an alkylamino group, an arylamino group or a heterocyclicgroup which may be substituted; c, d, e and f each represent an integerof 1 to 5; when they are 2 or more, R¹¹'s themselves, R¹²'s themselves,R¹⁶'s themselves or R¹⁷'s themselves may be the same as or differentfrom each other, and R¹¹'s themselves, R¹²'s themselves, R¹⁶'sthemselves or R¹⁷'s themselves may be combined with each other to form aring; R¹³ and R¹⁴ and R¹⁸ and R¹⁹ may be combined with each other toform rings; and L² represents a single bond, —O—, —S—, —N(R)— (R is analkyl group or an aryl group which may be substituted), an alkylenegroup or an arylene group).

Spirofluorene derivative represented by the following Formula (vii):

(wherein A⁵ to A⁸ each are independently a substituted ornon-substituted biphenylyl group or a substituted or non-substitutednaphthyl group).

Fused ring-containing compound represented by the following Formula(viii):

(wherein A⁹ to A¹⁴ are the same as those described above; R²¹ to R²³each represent independently a hydrogen atom, an alkyl group having 1 to6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, analkoxyl group having 1 to 6 carbon atoms, an aryloxy group having 5 to18 carbon atoms, an aralkyloxy group having 7 to 18 carbon atoms, anarylamino group having 5 to 16 carbon atoms, a nitro group, a cyanogroup, an ester group having 1 to 6 carbon atoms or a halogen atom; andat least one of A⁹ to A¹⁴ is a group having 3 or more fused aromaticrings).

Fluorene compound represented by the following Formula (ix):

(wherein R₁ and R₂ represent a hydrogen atom, a substituted ornon-substituted alkyl group, a substituted or non-substituted aralkylgroup, a substituted or non-substituted aryl group, a substituted ornon-substituted heterocyclic group, a substituted amino group, a cyanogroup or a halogen atom; R₁'s themselves and R₂'s themselves which arebonded to the different fluorene groups may be the same as or differentfrom each other, and R₁ and R₂ which are bonded to the same fluorenegroup may be the same or different; R₃ and R₄ represent a hydrogen atom,a substituted or non-substituted alkyl group, a substituted ornon-substituted aralkyl group, a substituted or non-substituted arylgroup or a substituted or non-substituted heterocyclic group; R₃'sthemselves and R₄'s themselves which are bonded to the differentfluorene groups may be the same as or different from each other, and R₃and R₄ which are bonded to the same fluorene group may be the same ordifferent; Ar₁ and Ar₂ represent a substituted or non-substituted fusedpolycyclic aromatic group in which the total of benzene rings is 3 ormore or a fused polycyclic heterocyclic group in which the total ofbenzene rings and heterocycles is 3 or more and which is bonded to afluorene group via substituted or non-substituted carbon; Ar₁ and Ar₂may be the same or different; and n represents an integer of 1 to 10).

Compound having an anthracene central skeleton represented by thefollowing Formula (x):

(in Formula (x), A₁ and A₂ each are independently a group derived from asubstituted or non-substituted aromatic ring having 6 to 20 ring carbonatoms; the aromatic ring described above may be substituted with atleast one substituent; the substituent described above is selected froma substituted or non-substituted aryl group having 6 to 50 ring carbonatoms, a substituted or non-substituted alkyl group having 1 to 50carbon atoms, a substituted or non-substituted cycloalkyl group having 3to 50 carbon atoms, a substituted or non-substituted alkoxy group having1 to 50 carbon atoms, a substituted or non-substituted aralkyl grouphaving 6 to 50 carbon atoms, a substituted or non-substituted aryloxygroup having 5 to 50 ring atoms, a substituted or non-substitutedarylthio group having 5 to 50 ring atoms, a substituted ornon-substituted alkoxycarbonyl group having 1 to 50 carbon atoms, asubstituted or non-substituted silyl group, a carboxyl group, a halogenatom, a cyano group, a nitro group and a hydroxyl group; when thearomatic ring described above is substituted with two or moresubstituents, the substituents described above may be the same ordifferent, and the adjacent substituents may be bonded with each otherto form a saturated or unsaturated cyclic structure;R₁ to R₈ each are independently selected from a hydrogen atom, asubstituted or non-substituted aryl group having 6 to 50 ring carbonatoms, a substituted or non-substituted heteroaryl group having 5 to 50ring atoms, a substituted or non-substituted alkyl group having 1 to 50carbon atoms, a substituted or non-substituted cycloalkyl group having 3to 50 carbon atoms, a substituted or non-substituted alkoxy group having1 to 50 carbon atoms, a substituted or non-substituted aralkyl grouphaving 6 to 50 carbon atoms, a substituted or non-substituted aryloxygroup having 5 to 50 ring atoms, a substituted or non-substitutedarylthio group having 5 to 50 ring atoms, a substituted ornon-substituted alkoxycarbonyl group having 1 to 50 carbon atoms, asubstituted or non-substituted silyl group, a carboxyl group, a halogenatom, a cyano group, a nitro group and a hydroxyl group).

Compound having a structure represented by the following Formula (xi) inwhich A₁ is different from A₂ in Formula (x) described above:

(in Formula (xi), A₁, A₂ and R₁ to R₈ each are independently the same asin Formula (x); provided that a case in which the groups symmetric to anX—Y axis shown on anthracene are bonded to a 9-position and a10-position of the above anthracene in a center is not present).

Among the host materials described above, the anthracene derivatives arepreferred; the monoanthracene derivatives are more preferred; and theasymmetric anthracenes are particularly preferred.

The host suited to phosphorescence comprising the compound containing acarbazole ring is a compound having a function in which transfer ofenergy from an excited state thereof to a phosphorescent compound takesplace to result in allowing the phosphorescent compound to emit light.The host compound shall not specifically be restricted as long as it isa compound which can transfer exciton energy to the phosphorescentcompound, and it can suitably be selected according to the purposes. Itmay have an optional heterocycle and the like in addition to a carbazolering.

The specific examples of the above host compound include carbazolederivatives, triazole derivatives, oxazole derivatives, oxadiazolederivatives, imidazole derivatives, polyarylalkane derivatives,pyrazoline derivatives, pyrazolone derivatives, phenylenediaminederivatives, arylamine derivatives, amino-substituted chalconederivatives, styrylanthracene derivatives, fluorenone derivatives,hydrazone derivatives, stilbene derivatives, silazane derivatives,aromatic tertiary amine compounds, styrylamine compounds, aromaticdimethylidene base compounds, porphyrin base compounds,anthraquinodimethane derivatives, anthrone derivatives, diphenylquinonederivatives, thiopyran dioxide derivatives, carbodiimide derivatives,fluorenilidenemethane derivatives, distyrylpyrazine derivatives,heterocyclic tetracarboxylic anhydride such as naphthaleneperylene andthe like, phthalocyanine derivatives, metal complexes of 8-quinolinolderivatives, various metal complex polysilane base compounds representedby metal complexes comprising metal phthalocyanine, benzoxazole andbenzothiazole as ligands, and high molecular compounds includingpoly(N-vinylcarbazole) derivatives, aniline base copolymers, thiopheneoligomers, electroconductive high molecular oligomers such aspolythiophene, polythiophene derivatives, polyphenylene derivatives,polyphenylenevinylene derivatives and polyfluorene derivatives. The hostcompounds may be used alone or in combination two or more kinds thereof.

The specific examples thereof include the following compounds:

The phosphorescent dopant is a compound which can emit light from atriplet exciton. It shall not specifically be restricted as long as itemits light from a triplet exciton. It is preferably a metal complexcontaining at least one metal selected from the group consisting of Ir,Ru, Pd, Pt, Os and Re, and a porphyrin metal complex or anortho-metallated metal complex is preferred. The porphyrin metal complexis preferably a porphyrin platinum complex. The phosphorescent compoundsmay be used alone or in combination of two or more kinds thereof.

A ligand forming the ortho-metallated metal complex includes variousones, and the preferred ligand includes 2-phenylpyridine derivatives,7,8-benzoquinoline derivatives, 2-(2-thienyl)pyridine derivatives,2-(1-naphthyl)pyridine derivatives, 2-phenylquinoline derivatives andthe like. The above derivatives may have, if necessary, substituents. Inparticular, the compounds into which fluorides and trifluoromethyl areintroduced are preferred as a blue color dopant. Further, it may have,as an auxiliary ligand, ligands other than the ligands described abovesuch as acetylacetonate, picric acid and the like.

A content of the phosphorescent dopant in the light emitting layer shallnot specifically be restricted, and it can suitably be selectedaccording to the purposes. It is, for example, 0.1 to 70 mass %,preferably 1 to 30 mass %. If a content of the phosphorescent dopant isless than 0.1 mass %, light emission is faint, and an addition effectthereof is not sufficiently exhibited. On the other hand, if it exceeds70 mass %, a phenomenon called concentration quenching is markedlybrought about, and the device performance is reduced.

The light emitting layer may contain, if necessary, a hole transportingmaterial, an electron transporting material and a polymer binder.

Further, a film thickness of the light emitting layer is preferably 5 to50 nm, more preferably 7 to 50 nm and most preferably 10 to 50 nm. If itis less than 5 nm, it is difficult to form the light emitting layer, andcontrolling of the chromaticity is likely to become difficult. On theother hand, if it exceeds 50 nm, the operating voltage is likely to goup.

(5) Hole Injecting and Transporting Layer (Hole Transporting Zone)

The hole injecting and transporting layer is a layer for assistinginjection of a hole into the light emitting layer to transport it to thelight emitting region, and it has a large hole mobility and showsusually as small ionization energy as 5.6 eV or less. A material whichtransports a hole to the light emitting layer by a lower electric fieldstrength is preferred for the above hole injecting and transportinglayer, and more preferred is a material in which a mobility of a hole isat least 10⁻⁴ cm²/V·second in applying an electric field of, forexample, 10⁴ to 10⁶ V/cm.

When the aromatic amine derivative of the present invention is used inthe hole transporting zone, the hole injecting and transporting layersmay be formed from the aromatic amine derivative of the presentinvention alone or it may be used in a mixture with other materials.

The materials for forming the hole injecting and transporting layer in amixture with the aromatic amine derivative of the present inventionshall not specifically be restricted as long as they have the preferredproperties described above, and capable of being used are optionalmaterials selected from materials which have so far conventionally beenused as charge transporting materials for holes in photoconductivematerials and publicly known materials which are used for a holeinjecting and transporting layer in an organic EL device. In the presentinvention, a material which has a hole transporting ability and whichcan be used for a hole transporting zone is called a hole transportingmaterial.

The specific examples thereof include triazole derivatives (refer toU.S. Pat. No. 3,112,197 and the like), oxadiazole derivatives (refer toU.S. Pat. No. 3,189,447 and the like), imidazole derivatives (refer toJapanese Patent Publication No. 16096/1962 and the like), polyarylalkanederivatives (refer to U.S. Pat. No. 3,615,402, ditto U.S. Pat. No.3,820,989 and ditto No. 3,542,544, Japanese Patent Publication No.555/1970 and ditto No. 10983/1976 and Japanese Patent ApplicationLaid-Open No. 93224/1976, ditto No. 17105/1980, ditto No. 4148/1981,ditto No. 108667/1980, ditto No. 156953/1980 and ditto No. 36656/1981and the like), pyrazoline derivatives and pyrazolone derivatives (referto U.S. Pat. No. 3,180,729 and ditto U.S. Pat. No. 4,278,746 andJapanese Patent Application Laid-Open No. 88064/1980, ditto No.88065/1980, ditto No. 105537/1974, ditto No. 51086/1980, ditto No.80051/1981, ditto No. 88141/1981, ditto No. 45545/1982, ditto No.112637/1979 and ditto No. 74546/1980 and the like), phenylenediaminederivatives (refer to U.S. Pat. No. 3,615,404, Japanese PatentPublication No. 10105/1976, ditto No. 3712/1971 and ditto No. 25336/1972and Japanese Patent Application Laid-Open No. 119925/1979 and the like),arylamine derivatives (refer to U.S. Pat. No. 3,567,450, ditto U.S. Pat.No. 3,240,597, ditto U.S. Pat. No. 3,658,520, ditto U.S. Pat. No.4,232,103, ditto U.S. Pat. No. 4,175,961 and ditto U.S. Pat. No.4,012,376, Japanese Patent Publication No. 35702/1974 and ditto No.27577/1964, Japanese Patent Application Laid-Open No. 144250/1980, dittoNo. 119132/1981 and ditto No. 22437/1981 and German Patent No. 1,110,518and the like), amino-substituted chalcone derivatives (refer to U.S.Pat. No. 3,526,501 and the like), oxazole derivatives (disclosed in U.S.Pat. No. 3,257,203 and the like), styrylanthracene derivatives (refer toJapanese Patent Application Laid-Open No. 46234/1981 and the like),fluorenone derivatives (refer to Japanese Patent Application Laid-OpenNo. 110837/1979 and the like), hydrazone derivatives (refer to U.S. Pat.No. 3,717,462, Japanese Patent Application Laid-Open No. 59143/1979,ditto No. 52063/1980, ditto No. 52064/1980, ditto No. 46760/1980, dittoNo. 11350/1982 and ditto No. 148749/1982, Japanese Patent ApplicationLaid-Open No. 311591/1990 and the like), stilbene derivatives (refer toJapanese Patent Application Laid-Open No. 210363/1986, ditto No.228451/1986, ditto No. 14642/1986, ditto No. 72255/1986, ditto No.47646/1987, ditto No. 36674/1987, ditto No. 10652/1987, ditto No.30255/1987, ditto No. 93455/1985, ditto No. 94462/1985, ditto No.174749/1985 and ditto No. 175052/1985 and the like), silazanederivatives (U.S. Pat. No. 4,950,950), polysilane base (Japanese PatentApplication Laid-Open No. 204996/1990), aniline base copolymers(Japanese Patent Application Laid-Open No. 282263/1990) and the like.

The compounds described above can be used as the material for the holeinjecting and transporting layer, and preferably used are porphyrincompounds (disclosed in Japanese Patent Application Laid-Open No.295695/1988 and the like), aromatic tertiary amine compounds andstyrylamine compounds (refer to U.S. Pat. No. 4,127,412 and JapanesePatent Application Laid-Open No. 27033/1978, ditto No. 58445/1979, dittoNo. 79450/1980, ditto No. 144250/1980, ditto No. 119132/1981, ditto No.295558/1986, ditto No. 98353/1986 and ditto No. 295695/1988 and thelike), and the aromatic tertiary amine compounds are particularlypreferably used.

Further, capable of being given are compounds having two fused aromaticrings in a molecule described in U.S. Pat. No. 5,061,569, for example,4,4′-bis(N-(1-naphthyl)-N-phenylamino)biphenyl (hereinafter abbreviatedas NPD) and 4,4′,4″-tris(N-(3-methylphenyl)-N-phenylamino)triphenylamine(hereinafter abbreviated as MTDATA) in which three triphenylamine unitsare combined in the form of a star burst type disclosed in JapanesePatent Application Laid-Open No. 308688/1992.

In addition to the above compounds, a nitrogen-containing heterocyclicderivative represented by the following formula which is disclosed inJapanese Patent No. 3571977 can be used as well:

(wherein R¹²¹ to R¹²⁶ each represent any of a substituted ornon-substituted alkyl group, a substituted or non-substituted arylgroup, a substituted or non-substituted aralkyl group and a substitutedor non-substituted heterocyclic group; provided that R¹²¹ to R¹²⁶ may bethe same or different; R¹²¹ and R¹²², R¹²³ and R¹²⁴, R¹²⁵ and R¹²⁶, R¹²¹and R¹²⁶, R¹²² and R¹²³ and R¹²⁴ and R²⁵ may form fused rings).

Further, a compound represented by the following formula which isdescribed in U.S. Patent Application Publication 2004/0113547 can beused as well:

(wherein R¹³¹ to R¹³⁶ are substituents and are preferably electronattractive groups such as a cyano group, a nitro group, a sulfonylgroup, a carbonyl group, a trifluoromethyl group, halogen and the like).

As represented by the above materials, acceptor materials can also beused as the hole injecting material. The specific examples thereof havebeen described above.

Further, inorganic compounds such as p type Si, p type SiC and the likecan also be used as the material for the hole injecting and transportinglayer in addition to the aromatic dimethylidene base compounds describedabove shown as the material for the light emitting layer.

The hole injecting and transporting layer can be formed by making a thinfilm from the aromatic amine derivative of the present invention by apublicly known method such as, for example, a vacuum vapor depositionmethod, a spin coating method, a casting method, an LB method and thelike. A film thickness of the hole injecting and transporting layershall not specifically be restricted, and it is usually 5 nm to 5 μm.The above hole injecting and transporting layer may be constituted froma single layer comprising at least one of the materials described aboveas long as the aromatic amine derivative of the present invention iscontained in the hole transporting zone, and a hole injecting andtransporting layer comprising a compound which is different from thecompound used in the hole injecting and transporting layer describedabove may be laminated thereon.

Further, an organic semiconductor layer may be provided as a layer forassisting injection of a hole into the light emitting layer, and thelayer having a conductance of 10⁻¹⁰ S/cm or more is suited. Capable ofbeing used as a material for the above organic semiconductor layer areconductive oligomers such as thiophene-containing oligomers andarylamine-containing oligomers disclosed in Japanese Patent ApplicationLaid-Open No. 193191/1996 and conductive dendrimers such asarylamine-containing dendrimers.

(6) Electron Injecting and Transporting Layer

The electron injecting and transporting layer is a layer for assistinginjection of an electron into the light emitting layer to transport itto the light emitting region, and it has a large electron mobility.Also, the adhesion improving layer is a layer comprising particularly amaterial having a good adhesive property with the cathode in the aboveelectron injecting layer.

It is known that since light emitted in an organic EL device isreflected by an electrode (in this case, a cathode), light emitteddirectly from an anode is interfered with light emitted via reflectionby the electrode. In order to make efficient use of the aboveinterference effect, the electron transporting layer is suitablyselected in a film thickness of several nm to several μm, andparticularly when the film thickness is large, the electron mobility ispreferably at least 10⁻⁵ cm²/Vs or more in applying an electric field of10⁴ to 10⁶ V in order to avoid a rise in voltage.

The materials used for the electron injecting layer are suitably metalcomplexes of 8-hyroxyquinoline or derivatives thereof and oxadiazolederivatives. The specific examples of the metal complexes of8-hyroxyquinoline or the derivatives thereof described above includemetal chelate oxynoid compounds containing chelates of oxine (ingeneral, 8-quinolinol or 8-hyroxyquinoline), and, for example,tris(8-quinolinol)aluminum can be used as the electron injectingmaterial.

On the other hand, the oxadiazole derivative includes electrontransmitting compounds represented by the following formulas:

(wherein Ar¹, Ar², Ar³, Ar⁵, Ar⁶ and Ar⁹ each represent a substituted ornon-substituted aryl group, and they may be the same as or differentfrom each other; Ar⁴, Ar⁷ and Ar⁸ each represent a substituted ornon-substituted arylene group, and they may be the same as or differentfrom each other).

In this connection, the aryl group includes phenyl, biphenylyl, anthryl,perylenyl and pyrenyl. Also, the arylene group includes phenylene,naphthylene, biphenylylene, anthrylene, perylenylene, pyrenylene and thelike. The substituents therefor include an alkyl group having 1 to 10carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano groupand the like. The above electron transmitting compounds have preferablya thin film-forming property.

The following compounds can be given as the specific examples of theelectron transmitting compounds described above:

Further, Compounds represented by the following Formulas (A) to (F) canalso be used as the materials used for the electron injecting layer andthe electron transporting layer.

Nitrogen-containing heterocyclic derivative represented by:

(in Formulas (A) and (B), A¹ to A³ each are independently a nitrogenatom or a carbon atom;in Formula (A), Ar¹ is a substituted or non-substituted aryl grouphaving 6 to 60 ring carbon atoms or a substituted or non-substitutedheteroaryl group having 3 to 60 ring carbon atoms;in Formula (B), Ar¹ is a divalent arylene group into which Ar¹ inFormula (A) is converted; Ar² is a hydrogen atom, a substituted ornon-substituted aryl group having 6 to 60 ring carbon atoms, asubstituted or non-substituted heteroaryl group having 3 to 60 ringcarbon atoms, a substituted or non-substituted alkyl group having 1 to20 carbon atoms or a substituted or non-substituted alkoxy group having1 to 20 carbon atoms or a divalent group thereof; provided that eitherone of Ar¹ and Ar² is a substituted or non-substituted fused ring grouphaving 10 to 60 ring carbon atoms or a substituted or non-substitutedmonohetero fused ring group having 3 to 60 ring carbon atoms or adivalent group thereof;L₁, L₂ and L each are independently a single bond, a substituted ornon-substituted arylene group having 6 to 60 ring carbon atoms, asubstituted or non-substituted heteroarylene group having 3 to 60 ringcarbon atoms or a substituted or non-substituted fluorenylene group;R is a hydrogen atom, a substituted or non-substituted aryl group having6 to 60 ring carbon atoms, a substituted or non-substituted heteroarylgroup having 3 to 60 ring carbon atoms, a substituted or non-substitutedalkyl group having 1 to 20 carbon atoms or a substituted ornon-substituted alkoxy group having 1 to 20 carbon atoms; n is aninteger of 0 to 5; when n is 2 or more, plural R's may be the same ordifferent, and adjacent plural R's may be combined with each other toform a carbocyclic aliphatic ring or a carbocyclic aromatic ring;R¹ is a hydrogen atom, a substituted or non-substituted aryl grouphaving 6 to 60 ring carbon atoms, a substituted or non-substitutedheteroaryl group having 3 to 60 ring carbon atoms, a substituted ornon-substituted alkyl group having 1 to 20 carbon atoms, a substitutedor non-substituted alkoxy group having 1 to 20 carbon atoms or-L-Ar¹—Ar²).

Nitrogen-containing heterocyclic derivative represented by:HAr-L-Ar¹—Ar²  (C)(wherein HAr is a nitrogen-containing heterocycle having 3 to 40 carbonatoms which may have a substituent; L is a single bond, an arylene grouphaving 6 to 60 carbon atoms which may have a substituent, aheteroarylene group having 3 to 60 carbon atoms which may have asubstituent or a fluorenylene group which may have a substituent; Ar¹ isa divalent aromatic hydrocarbon group having 6 to 60 carbon atoms whichmay have a substituent; and Ar² is an aryl group having 6 to 60 carbonatoms which may have a substituent or a heteroaryl group having 3 to 60carbon atoms which may have a substituent).

Silacyclopentadiene derivative represented by:

(wherein X and Y each are independently a saturated or unsaturatedhydrocarbon group having 1 to 6 carbon atoms, an alkoxy group, analkenyloxy group, an alkynyloxy group, a hydroxy group, a substituted ornon-substituted aryl group, a substituted or non-substituted heterocycleor a structure in which X is combined with Y to form a saturated orunsaturated ring; R¹ to R⁴ each are independently a hydrogen atom, ahalogen atom, a substituted or non-substituted alkyl group having 1 to 6carbon atoms, an alkoxy group, an aryloxy group, a perfluoroalkyl group,a perfluoroalkoxy group, an amino group, an alkylcarbonyl group, anarylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group,an azo group, an alkylcarbonyloxy group, an arylcarbonyloxy group, analkoxycarbonyloxy group, an aryloxycarbonyloxy group, a sulfinyl group,a sulfonyl group, a sulfanyl group, a silyl group, a carbamoyl group, anaryl group, a heterocyclic group, an alkenyl group, an alkynyl group, anitro group, a formyl group, a nitroso group, a formyloxy group, anisocyano group, a cyanate group, an isocyanate group, a thiocyanategroup, an isothiocyanate group, a cyano group or a structure in whichwhen two substituents are adjacent, they are bonded with each other toform a substituted or non-substituted, saturated or unsaturated ring).

Borane derivative represented by:

(wherein R₁ to R₈ and Z₂ each represent independently a hydrogen atom, asaturated or unsaturated hydrocarbon group, an aromatic group, aheterocyclic group, a substituted amino group, a substituted borylgroup, an alkoxy group or an aryloxy group; X, Y and Z₁ each representindependently a saturated or unsaturated hydrocarbon group, an aromaticgroup, a heterocyclic group, a substituted amino group, an alkoxy groupor an aryloxy group; substituents of Z₁ and Z₂ may be combined with eachother to form a fused ring; n represents an integer of 1 to 3, and whenn is 2 or more, Z₁'s may be different; provided that a case in which nis 1 and X, Y and R₂ are methyl and in which R₈ is a hydrogen atom or asubstituted boryl group and a case in which n is 3 and in which Z₁ ismethyl are not included therein).

[wherein Q¹ and Q² each represent independently a ligand represented bythe following Formula (G), and L represents a halogen atom, asubstituted or non-substituted alkyl group, a substituted ornon-substituted cycloalkyl group, a substituted or non-substituted arylgroup, a substituted or non-substituted heterocyclic group, —OR¹ (R¹ isa hydrogen atom, a substituted or non-substituted alkyl group, asubstituted or non-substituted cycloalkyl group, a substituted ornon-substituted aryl group or a substituted or non-substitutedheterocyclic group) or a ligand represented by —O—Ga-Q³(Q⁴) (Q³ and Q⁴are the same as Q¹ and Q²)]:

[wherein rings A¹ and A² assume a six-membered aryl ring structure whichmay have a substituent and in which they are fused with each other].

The above metal complex has a strong property of an n type semiconductorand is provided with a large electron injecting ability. Further, sinceit has low production energy in forming the complex, a bonding propertybetween the metal and the ligand in the metal complex formed becomesfirm, and a fluorescence quantum efficiency thereof as the lightemitting material grows larger as well.

The specific examples of substituents for the rings A¹ and A² formingthe ligand represented by Formula (G) include a halogen atom such aschlorine, bromine, iodine and fluorine, a substituted or non-substitutedalkyl group such as methyl, ethyl, propyl, butyl, s-butyl, t-butyl,pentyl, hexyl, heptyl, octyl, stearyl, trichloromethyl and the like, asubstituted or non-substituted aryl group such as phenyl, naphthyl,3-methylphenyl, 3-methoxyphenyl, 3-fluorophenyl,3-trichloromethylphenyl, 3-trifluoromethylphenyl, 3-nitrophenyl and thelike, a substituted or non-substituted alkoxy group such as methoxy,n-butoxy, t-butoxy, trichloromethoxy, trifluoroethoxy,pentafluoropropoxy, 2,2,3,3-tetrafluoropropoxy,1,1,1,3,3,3-hexafluoro-2-propoxy, 6-(perfluoroethyl)hexyloxy and thelike, a substituted or non-substituted aryloxy group such as phenoxy,p-nitrophenoxy, p-t-butylphenoxy, 3-fluorophenoxy, pentafluorophenoxy,3-trifluoromethylphenoxy and the like, a substituted or non-substitutedalkylthio group such as methylthio, ethylthio, t-butylthio, hexylthio,octylthio, trifluoromethylthio and the like, a substituted ornon-substituted arylthio group such as phenylthio, p-nitrophenylthio,p-t-butylphenylthio, 3-fluorophenylthio, pentafluorophenylthio,3-trifluoromethylphenylthio and the like, a cyano group, a nitro group,an amino group, a mono- or disubstituted amino group such asmethylamino, diethylamino, ethylamino, diethylamino, dipropylamino,dibutylamino, diphenylamino and the like, an acylamino group such asbis(acetoxymethyl)amino, bis(acetoxyethyl)amino,bis(acetoxypropyl)amino, bis(acetoxybutyl)amino and the like, a hydroxylgroup, a siloxy group, an acyl group, a carbamoyl group such asmethylcarbamoyl, dimethylcarbamoyl, ethylcarbamoyl, diethylcarbamoyl,propylcarbamoyl, butylcarbamoyl, phenylcarbamoyl and the like, acarboxylic acid group, a sulfonic acid group, an imide group, acycloalkyl group such as cyclopentane, cyclohexyl and the like, an arylgroup such as phenyl, naphthyl, biphenylyl, anthryl, phenanthryl,fluorenyl, pyrenyl and the like and a heterocyclic group such aspyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, indolinyl,quinolinyl, acridinyl, pyrrolidinyl, dioxanyl, piperidinyl,morpholidinyl, piperazinyl, carbazolyl, furanyl, thiophenyl, oxazolyl,oxadiazolyl, benzoxazolyl, thiazolyl, thiadiazolyl, benzothiazolyl,triazolyl, imidazolyl, benzimidazolyl, furanyl and the like. Further,the substituents described above may be combined with each other to formsix-membered aryl rings or heterocycles.

The preferred mode of the organic EL device of the present inventionincludes a device containing a reducing dopant in the region whichtransports an electron or an interfacial region between the cathode andthe organic layer. In this case, the reducing dopant is defined by asubstance which can reduce an electron transporting compound.Accordingly, various compounds can be used as long as they have acertain reducing property, and capable of being suitably used is atleast one substance selected from the group consisting of, for example,alkali metals, alkaline earth metals, rare earth metals, oxides ofalkali metals, halides of alkali metals, oxides of alkaline earthmetals, halides of alkaline earth metals, oxides of rare earth metals orhalides of rare earth metals, organic complexes of alkali metals,organic complexes of alkaline earth metals and organic complexes of rareearth metals.

To be more specific, the preferred reducing dopant includes at least onealkali metal selected from the group consisting of Li (work function:2.9 eV), Na (work function: 2.36 eV), K (work function: 2.28 eV), Rb(work function: 2.16 eV) and Cs (work function: 1.95 eV) and at leastone alkali earth metal selected from the group consisting of Ca (workfunction: 2.9 eV), Sr (work function: 2.0 to 2.5 eV) and Ba (workfunction: 2.52 eV), and the compounds having a work function of 2.9 eVor less are particularly preferred. Among them, the more preferredreducing dopant is at least one alkali metal selected from the groupconsisting of K, Rb and Cs, and it is more preferably Rb or Cs. It ismost preferably Cs. The above alkali metals have a particularly highreducing ability, and addition of a relatively small amount thereof tothe electron injecting zone makes it possible to raise a light emittingluminance in the organic EL device and extend a lifetime thereof. Thecombination of two or more kinds of the above alkali metals is preferredas the reducing dopant having a work function of 2.9 eV or less, andparticularly preferred is the combination containing Cs, for example,the combination of Cs with Na, Cs with K, Cs with Rb or Cs with Na andK. Containing Cs in combination makes it possible to efficiently exhibitthe reducing ability, and addition thereof to the electron injectingzone makes it possible to enhance a light emitting luminance in theorganic EL device and extend a lifetime thereof.

In the present invention, an electron injecting layer constituted froman insulator and a semiconductor may further be provided between thecathode and the organic layer. In this case, an electric current caneffectively be prevented from leaking to enhance the electron injectingproperty. Preferably used as the above insulator is at least one metalcompound selected from the group consisting of alkali metalchalcogenides, alkaline earth metal chalcogenides, halides of alkalimetals and halides of alkaline earth metals. If the electron injectinglayer is constituted from the above alkali metal chalcogenides and thelike, it is preferred from the viewpoint that the electron injectingproperty can further be enhanced. To be specific, the preferred alkalimetal chalcogenides include, for example, Li₂O, K₂O, Na₂S, Na₂Se andNa₂O, and the preferred alkaline earth metal chalcogenides include, forexample, CaO, BaO, SrO, BeO, BaS and CaSe. Also, the preferred halidesof alkali metals include, for example, LiF, NaF, KF, LiCl, KCl and NaCl.Further, the preferred halides of alkaline earth metals include, forexample, fluorides such as CaF₂, BaF₂, SrF₂, MgF₂ and BeF₂ and halidesother than the fluorides.

The semiconductor constituting the electron transporting layer includesa single kind of oxides, nitrides or nitride oxides containing at leastone element of Ba, Ca, Sr, Yb, Al, Ga, In, Li, Na, Cd, Mg, Si, Ta, Sband Zn or combinations of two or more kinds thereof. The inorganiccompound constituting the electron transporting layer is preferably acrystallite or amorphous insulating thin film. If the electrontransporting layer is constituted from the above insulating thin film,the more homogeneous thin film is formed, and therefore picture elementdefects such as dark spots can be reduced. The above inorganic compoundincludes the alkali metal chalcogenides, the alkaline earth metalchalcogenides, the halides of alkali metals and the halides of alkalineearth metals each described above.

(7) Cathode

Cathodes prepared by using metals, alloys, electroconductive compoundsand mixtures thereof each having a small work function (4 eV or less)for electrode materials are used as the cathode in order to injectelectrons into the electron injecting and transporting layer or thelight emitting layer. The specific examples of the above electrodematerials include sodium, sodium•potassium alloys, magnesium, lithium,magnesium•silver alloys, aluminum/aluminum oxide, aluminum•lithiumalloys, indium, rare earth metals and the like.

The above cathode can be prepared by forming a thin film from the aboveelectrode materials by a method such as vapor deposition, sputtering andthe like.

In this respect, when light emitted from the light emitting layer istaken out from the cathode, a light transmittance of the cathode basedon light emitted is preferably larger than 10%.

A sheet resistance of the cathode is preferably several hundred Ω/□ orless, and a film thickness thereof is usually 10 nm to 1 μm, preferably50 to 200 nm.

(8) Insulating Layer

The organic EL device is liable to cause picture element defects by leakand short since an electric field is applied to a ultrathin film. Inorder to prevent the above matter, an insulating thin film layer ispreferably interposed between a pair of the electrodes.

A material used for the insulating layer includes, for example, aluminumoxide, lithium fluoride, lithium oxide, cesium fluoride, cesium oxide,magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride,aluminum nitride, titanium oxide, silicon oxide, germanium oxide,silicon nitride, boron nitride, molybdenum oxide, ruthenium oxide,vanadium oxide and the like, and mixtures and laminates thereof may beused as well.

(9) Production Process for Organic EL Device

According to the materials and the forming methods which have been shownabove as the examples, the anode, the light emitting layer, ifnecessary, the hole injecting and transporting layer and, if necessary,the electron injecting and transporting layer are formed, and furtherthe cathode is formed, whereby the organic EL device can be prepared.Also, the organic EL device can be prepared as well in an order of fromthe cathode to the anode which is reverse to the order described above.

A preparation example of an organic EL device having a structure inwhich an anode/a hole injecting layer/a light emitting layer/an electroninjecting layer/a cathode are provided in order on a light transmittingsubstrate shall be described below.

First, a thin film comprising an anode material is formed on a suitablelight transmitting substrate by a method such as vapor deposition,sputtering and the like so that a film thickness falling in a range of 1μm or less, preferably 10 to 200 nm is obtained, whereby an anode isprepared. Next, a hole injecting layer is provided on the above anode.The hole injecting layer can be formed, as described above, by a methodsuch as a vacuum vapor deposition method, a spin coating method, acasting method, an LB method and the like, and it is formed preferablyby the vacuum vapor deposition method from the viewpoints that thehomogeneous film is liable to be obtained and that pinholes are lessliable to be produced. When forming the hole injecting layer by thevacuum vapor deposition method, the depositing conditions thereof arevaried according to the compounds used (materials for the hole injectinglayer), the crystal structure of the targeted hole injecting layer andthe recombination structure, and in general, they are suitably selectedpreferably in the ranges of a depositing source temperature of 50 to450° C., a vacuum degree of 10⁻⁷ to 10⁻³ Torr, a depositing speed of0.01 to 50 nm/second, a substrate temperature of −50 to 300° C. and afilm thickness of 5 nm to 5 μm.

Next, a light emitting layer can be formed on the hole injecting layerby making a thin film from the desired organic light emitting materialby a method such as a vacuum vapor deposition method, sputtering, a spincoating method, a casting method and the like, and it is formedpreferably by the vacuum vapor deposition method from the viewpointsthat the homogeneous film is liable to be obtained and that pinholes areless liable to be produced. When forming the light emitting layer by thevacuum vapor deposition method, the depositing conditions thereof arevaried according to the compounds used, and in general, they can beselected from the same condition ranges as in the hole injecting layer.

Next, an electron injecting layer is provided on the above lightemitting layer. It is formed preferably by the vacuum vapor depositionmethod as in the case with the hole injecting layer and the lightemitting layer since the homogeneous film has to be obtained. Thedepositing conditions thereof can be selected from the same conditionranges as in the hole injecting layer and the light emitting layer.

The aromatic amine derivative of the present invention can becodeposited together with the other materials, though varied dependingon that it is added to any layer of the light emitting zone and the holetransporting zone, when using the vacuum vapor deposition method. Whenusing the spin coating method, it can be added by mixing with the othermaterials.

Lastly, a cathode is laminated, whereby an organic EL device can beobtained.

The cathode is constituted from metal, and therefore the vapordeposition method and the sputtering method can be used. However, thevacuum vapor deposition method is preferred in order to protect theorganic substance layer of the base from being damaged in making thefilm.

The above organic EL device is preferably prepared serially from theanode up to the cathode after vacuuming once.

The forming methods of the respective layers in the organic EL device ofthe present invention shall not specifically be restricted, and formingmethods carried out by a vacuum vapor deposition method, a spin coatingmethod and the like which have so far publicly been known can be used.The organic thin film layer containing the compound represented byFormula (1) described above which is used for the organic EL device ofthe present invention can be formed by a publicly known method carriedout by a vacuum vapor deposition method, a molecular beam epitaxy method(MBE method) and a coating method such as a dipping method using asolution prepared by dissolving the compound in a solvent, a spincoating method, a casting method, a bar coating method and a rollcoating method.

The film thicknesses of the respective organic layers in the organic ELdevice of the present invention shall not specifically be restricted,and in general, if the film thicknesses are too small, defects such aspinholes are liable to be caused. On the other hand, if they are toolarge, high voltage has to be applied, and the efficiency isdeteriorated, so that they fall usually in a range of preferably severalnm to 1 μm.

When applying a direct voltage to the organic EL device, light emissioncan be observed by applying a voltage of 5 to 40 V setting a polarity ofthe anode to plus and that of the cathode to minus. An electric currentdoes not flow by applying a voltage at a reverse polarity, and lightemission is not caused at all. Further, when applying an AC voltage,uniform light emission can be observed only when the anode has a pluspolarity and the cathode has a minus polarity. A waveform of analternating current applied may be optional.

EXAMPLES

The present invention shall be explained below in further details withreference to synthetic examples and examples. Intermediates 1 to 21produced in Synthetic Examples 1 to 21 have the following structures:

Synthetic Example 1 Synthesis of Intermediate 1

A three neck flask of 1000 mL was charged with 47 g of 4-bromobiphenyl,23 g of iodine, 9.4 g of periodic acid dihydrate, 42 ml of water, 360 mLof acetic acid and 11 mL of sulfuric acid under argon flow, and themixture was stirred at 65° C. for 30 minutes and then reacted at 90° C.for 6 hours. The reaction product was poured into ice and water andfiltered. The filtered matter was washed with water and then withmethanol, whereby 67 g of a white powder was obtained. The principalpeaks of m/z=358 and 360 versus C₁₂H₁₅BrI=359 were obtained by analysisof FD-MS (field desorption mass spectrum), and therefore it wasidentified as Intermediate 1.

Synthetic Example 2 Synthesis of Intermediate 2

A three neck flask of 300 mL was charged with 10 g of p-terphenyl, 12 gof iodine, 4.9 g of periodic acid dihydrate, 20 mL of water, 170 mL ofacetic acid and 22 mL of sulfuric acid under argon flow, and the mixturewas stirred at 65° C. for 30 minutes and then reacted at 90° C. for 6hours. The reaction product was poured into ice and water and filtered.The filtered matter was washed with water and then with methanol,whereby 18 g of a white powder was obtained. The principal peak ofm/z=482 versus C₁₈H₁₂I₂=482 was obtained by analysis of FD-MS, andtherefore it was identified as Intermediate 2.

Synthetic Example 3 Synthesis of Intermediate 3

A reaction vessel of 50 L was charged with 750 g of phenylboronic acid,1000 g of 2-bromothiophene, 142 g oftetrakis(triphenylphosphine)palladium (Pd(PPh₃)₄), 9 L of a 2 M solutionof sodium carbonate (Na₂CO₃) and 15 L of dimethoxyethane under argonflow, and then they were reacted at 80° C. for 8 hours. The reactionsolution was extracted with toluene/water, and the extract was dried onanhydrous sodium sulfate. This was concentrated under reduced pressure,and a crude product obtained was refined through a column, whereby 786 gof a white powder was obtained.

A reaction vessel of 20 L was charged with 786 g of the compoundobtained above and 8 L of DMF (dimethylforamide) under argon flow, andthen 960 g of NBS (N-bromosuccinimide) was slowly added thereto to carryout reaction at room temperature for 12 hours. The reaction solution wasextracted with hexane/water, and the extract was dried on anhydroussodium sulfate. This was concentrated under reduced pressure, and acrude product obtained was refined through a column, whereby 703 g of awhite powder was obtained. It was identified as Intermediate 3 byanalysis of FD-MS.

Synthetic Example 4 Synthesis of Intermediate 4

A reaction vessel of 20 L was charged with 703 g of Intermediate 3 and 7L of anhydrous THF (tetrahydrofuran) under argon flow and cooled down to−30° C. n-Butyhllithium (n-BuLi, 1.6 M hexane solution) 2.3 L was addedthereto to carry out reaction for one hour. After cooled down to −70°C., 1658 g of triisopropyl borate (manufactured by Tokyo Kasei KogyoCo., Ltd.) was added thereto. The solution was slowly heated and stirredat room temperature for one hour. A 10% hydrochloric acid solution 1.7 Lwas added thereto and stirred. The reaction solution was extracted withethyl acetate and water, and the organic layer was washed with water.The organic layer was dried on anhydrous sodium sulfate, and the solventwas removed by distillation. The residue was washed with hexane, whereby359 g of a white powder was obtained.

A reaction vessel of 20 L was charged with 506 g of5-phenyl-2-thiopheneboronic acid obtained above, 600 g of4-iodobromobenzene, 41 g of tetrakis(triphenylphosphine)-palladium(Pd(PPh₃)₄), 2.6 L of a 2 M solution of sodium carbonate (Na₂CO₃) and 10L of dimethoxyethane under argon flow, and then they were reacted at 80°C. for 8 hours. The reaction solution was extracted with toluene/water,and the extract was dried on anhydrous sodium sulfate. This wasconcentrated under reduced pressure, and a crude product obtained wasrefined through a column, whereby 277 g of a white powder was obtained.It was identified as Intermediate 4 by analysis of FD-MS.

Synthetic Example 5 Synthesis of Intermediate 5

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 4, Intermediate 1 was used in place of 4-iodobromobenzene,whereby 342 g of a white powder was obtained. It was identified asIntermediate 5 by analysis of FD-MS.

Synthetic Example 6 Synthesis of Intermediate 6

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 4,5-methyl-2-thiopheneboronic acid was used in place of5-phenyl-2-thiopheneboronic acid, whereby 203 g of a white powder wasobtained. It was identified as Intermediate 6 by analysis of FD-MS.

Synthetic Example 7 Synthesis of Intermediate 8

A flask was charged with 5.5 g of aniline, 15.7 g of Intermediate 4, 6.8g of sodium t-butoxide (manufactured by Hiroshima Wako Co., Ltd.), 0.46g of tris(dibenzylideneacetone)dipalladium(O) (manufactured by AldrichCo., Ltd.) and 300 mL of anhydrous toluene under argon flow to carry outreaction at 80° C. for 8 hours.

After cooling down, 500 mL of water was added thereto, and the mixturewas filtered through celite. The filtrate was extracted with toluene,and the extract was dried on anhydrous magnesium sulfate. This wasconcentrated under reduced pressure, and a crude product obtained wasrefined through a column and recrystallized from toluene. It wasseparated by filtration and then dried, whereby 10.8 g of a pale yellowpowder was obtained. It was identified as Intermediate 8 by analysis ofFD-MS.

Synthetic Example 8 Synthesis of Intermediate 9

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 8, Intermediate 6 was used in place of Intermediate 4,whereby 7.3 g of a white powder was obtained. It was identified asIntermediate 9 by analysis of FD-MS.

Synthetic Example 9 Synthesis of Intermediate 11

A flask was charged with 185 g of acetamide (manufactured by Tokyo KaseiKogyo Co., Ltd.), 315 g of Intermediate 4 (manufactured by Wako PureChemical Industries, Ltd.), 544 g of potassium carbonate (manufacturedby Wako Pure Chemical Industries, Ltd.), 12.5 g of copper powder(manufactured by Wako Pure Chemical Industries, Ltd.) and 2 L of decalinunder argon flow to carry out reaction at 190° C. for 4 days. Thereaction solution was cooled down after finishing the reaction, and 2 Lof toluene was added to obtain insoluble matters by filtration. Thefiltered matter was dissolved in 4.5 L of chloroform to remove insolublematters, and then the solution was subjected to treatment with activatedcarbon and concentrated. Acetone 3 L was added thereto to obtain 175 gof deposited crystal by filtration.

This was suspended in 5 L of ethylene glycol (manufactured by Wako PureChemical Industries, Ltd.) and 50 mL of water, and 210 g of a 85%potassium hydroxide aqueous solution was added thereto, followed bycarrying out reaction at 120° C. for 8 hours. After finishing thereaction, the reaction liquid was poured into 10 L of water, anddeposited crystal was obtained by filtration and washed with water andmethanol. The crystal thus obtained was dissolved in 3 L oftetrahydrofuran by heating. The solution was treated with activatedcarbon and then concentrated, and acetone was added thereto to depositcrystal. This was separated by filtration to obtain 145 g of a whitepowder. It was identified as Intermediate 11 by analysis of FD-MS.

Synthetic Example 10 Synthesis of Intermediate 12

A flask was charged with 185 g of acetamide (manufactured by Tokyo KaseiKogyo Co., Ltd.), 253 g of 4-bromobiphenyl (manufactured by Wako PureChemical Industries, Ltd.), 544 g of potassium carbonate (manufacturedby Wako Pure Chemical Industries, Ltd.), 12.5 g of copper powder(manufactured by Wako Pure Chemical Industries, Ltd.) and 2 L of decalinunder argon flow to carry out reaction at 190° C. for 4 days. Thereaction solution was cooled down after finishing the reaction, and 2 Lof toluene was added to obtain insoluble matters by filtration. Thefiltered matter was dissolved in 4.5 L of chloroform to remove insolublematters, and then the solution was subjected to treatment with activatedcarbon and concentrated. Acetone 3 L was added thereto to obtain 205 gof deposited crystal by filtration.

Added thereto were 177 g of Intermediate 4, 380 g of potassium carbonate(manufactured by Wako Pure Chemical Industries, Ltd.), 8.8 g of copperpowder (manufactured by Wako Pure Chemical Industries, Ltd.) and 2 L ofdecalin, and they were reacted at 190° C. for 4 days. The reactionsolution was cooled down after finishing the reaction, and 1.4 L oftoluene was added to obtain insoluble matters by filtration. Thefiltered matter was dissolved in 3 L of chloroform to remove insolublematters, and then the solution was subjected to treatment with activatedcarbon and concentrated. Acetone 3 L was added thereto to obtain 224 gof deposited crystal by filtration. This was suspended in 3.5 L ofethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.)and 35 mL of water, and 147 g of a 85% potassium hydroxide aqueoussolution was added thereto, followed by carrying out reaction at 120° C.for 8 hours. After finishing the reaction, the reaction liquid waspoured into 10 L of water, and deposited crystal was obtained byfiltration and washed with water and methanol. The crystal thus obtainedwas dissolved in 3 L of tetrahydrofuran by heating. The solution wastreated with activated carbon and then concentrated, and acetone wasadded thereto to deposit crystal. This was separated by filtration toobtain 141 g of a white powder. It was identified as Intermediate 12 byanalysis of FD-MS.

Synthetic Example 11 Synthesis of Intermediate 13

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 11, an amount of Intermediate 4 was changed from 315 g to630 g, whereby 240 g of a white powder was obtained. It was identifiedas Intermediate 13 by analysis of FD-MS.

Synthetic Example 12 Synthesis of Intermediate 14

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 13, Intermediate 6 was used in place of Intermediate 4,whereby 140 g of a white powder was obtained. It was identified asIntermediate 14 by analysis of FD-MS.

Synthetic Example 13 Synthesis of Intermediate 16

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 8, Intermediate 11 was used in place of aniline and that1-bromonaphthalene was used in place of Intermediate 4, whereby 12 g ofa white powder was obtained. It was identified as Intermediate 16 byanalysis of FD-MS.

Synthetic Example 14 Synthesis of Intermediate 17

A flask was charged with 185 g of acetamide (manufactured by Tokyo KaseiKogyo Co., Ltd.), 315 g of Intermediate 4 (manufactured by Wako PureChemical Industries, Ltd.), 544 g of potassium carbonate (manufacturedby Wako Pure Chemical Industries, Ltd.), 12.5 g of copper powder(manufactured by Wako Pure Chemical Industries, Ltd.) and 2 L of decalinunder argon flow to carry out reaction at 190° C. for 4 days. Thereaction solution was cooled down after finishing the reaction, and 2 Lof toluene was added to obtain insoluble matters by filtration. Thefiltered matter was dissolved in 4.5 L of chloroform to remove insolublematters, and then the solution was subjected to treatment with activatedcarbon and concentrated. Acetone 3 L was added thereto to obtain 175 gof deposited crystal by filtration.

Added thereto were 120 g of 4,4′-diiodobiphenyl (manufactured by WakoPure Chemical Industries, Ltd.), 163 g of potassium carbonate(manufactured by Wako Pure Chemical Industries, Ltd.), 3.8 g of copperpowder (manufactured by Wako Pure Chemical Industries, Ltd.) and 600 mLof decalin, and they were reacted at 190° C. for 4 days.

The reaction solution was cooled down after finishing the reaction, and600 mL of toluene was added thereto to obtain insoluble matters byfiltration. The filtered matter was dissolved in 1.4 L of chloroform toremove insoluble matters, and then the solution was subjected totreatment with activated carbon and concentrated. Acetone 1 L was addedthereto to obtain 382 g of deposited crystal by filtration.

This was suspended in 1.5 L of ethylene glycol (manufactured by WakoPure Chemical Industries, Ltd.) and 15 mL of water, and 44 g of a 85%potassium hydroxide aqueous solution was added thereto, followed bycarrying out reaction at 120° C. for 8 hours. After finishing thereaction, the reaction liquid was poured into 10 L of water, anddeposited crystal was obtained by filtration and washed with water andmethanol. The crystal thus obtained was dissolved in 1 L oftetrahydrofuran by heating. The solution was treated with activatedcarbon and then concentrated, and acetone was added thereto to depositcrystal. This was separated by filtration to obtain 130 g of a whitepowder. It was identified as Intermediate 17 by analysis of FD-MS.

Synthetic Example 15 Synthesis of Intermediate 18

A flask was charged with 547 g of 1-acetamidenaphthalene (manufacturedby Tokyo Kasei Kogyo Co., Ltd.), 400 g of 4,4′-diiodobiphenyl(manufactured by Wako Pure Chemical Industries, Ltd.), 544 g ofpotassium carbonate (manufactured by Wako Pure Chemical Industries,Ltd.), 12.5 g of copper powder (manufactured by Wako Pure ChemicalIndustries, Ltd.) and 2 L of decalin under argon flow to carry outreaction at 190° C. for 4 days.

The reaction solution was cooled down after finishing the reaction, and2 L of toluene was added thereto to obtain insoluble matters byfiltration. The filtered matter was dissolved in 4.5 L of chloroform toremove insoluble matters, and then it was subjected to treatment withactivated carbon and concentrated. Acetone 3 L was added thereto toobtain 382 g of deposited crystal by filtration. This was suspended in 5L of ethylene glycol (manufactured by Wako Pure Chemical Industries,Ltd.) and 50 mL of water, and 145 g of a 85% potassium hydroxide aqueoussolution was added thereto, followed by carrying out reaction at 120° C.for 8 hours. After finishing the reaction, the reaction liquid waspoured into 10 L of water, and deposited crystal was obtained byfiltration and washed with water and methanol. The crystal thus obtainedwas dissolved in 3 L of tetrahydrofuran by heating. The solution wastreated with activated carbon and then concentrated, and acetone wasadded thereto to deposit crystal. This was separated by filtration toobtain 264 g of a white powder. It was identified as Intermediate 18 byanalysis of FD-MS.

Synthetic Example 16 Synthesis of Intermediate 19

A flask was charged with 5.1 g of diphenylamine, 10.8 g of Intermediate1, 3 g of sodium t-butoxide (manufactured by Hiroshima Wako Co., Ltd.),0.5 g of bis(triphenyl-phosphine)palladium(II) chloride (manufactured byTokyo Kasei Kogyo Co., Ltd.) and 500 mL of xylene under argon flow tocarry out reaction at 130° C. for 24 hours.

After cooling down, 1000 mL of water was added thereto, and the mixturewas filtered through celite. The filtrate was extracted with toluene,and the extract was dried on anhydrous magnesium sulfate. This wasconcentrated under reduced pressure, and a crude product obtained wasrefined through a column and recrystallized from toluene. It wasseparated by filtration and then dried, whereby 3.4 g of a pale yellowpowder was obtained. It was identified as Intermediate 19 by analysis ofFD-MS.

Synthetic Example 17 Synthesis of Intermediate 20

Reaction was carried out in the same manner, except that in synthesis ofIntermediate 19, 4-iodobromobenzene was used in place of Intermediate 1,whereby 2.8 g of a white powder was obtained. It was identified asIntermediate 20 by analysis of FD-MS.

Synthetic Example 18 Synthesis of Intermediate 21

A three neck flask of 200 mL was charged with 20.0 g of 4-bromobiphenyl(manufactured by Tokyo Kasei Kogyo Co., Ltd.), 8.64 g of sodiumt-butoxide (manufactured by Wako Pure Chemical Industries, Ltd.) and 84mg of palladium acetate (manufactured by Wako Pure Chemical Industries,Ltd.). Further, a stirring rod was put therein, and rubber caps were setat both sides of the flask. A condenser for refluxing was set in theneck of the center, and a three-way cock and a balloon charged withargon gas were set thereon to substitute the inside of the system threetimes with the argon gas in the balloon by means of a vacuum pump.

Next, 120 mL of anhydrous toluene (manufactured by Hiroshima Wako Co.,Ltd.), 4.08 mL of benzylamine (manufactured by Tokyo Kasei Kogyo Co.,Ltd.) and 338 μL of tris-t-butylphsosphine (a 2.22 mol/L toluenesolution, manufactured by Aldrich Co., Ltd.) were added thereto througha rubber septum by means of a syringe and stirred at room temperaturefor 5 minutes. Next, the flask was set on an oil bath and graduallyheated up to 120° C. while stirring the solution. After 7 hours passed,the flask was taken off from the oil bath to terminate the reaction, andit was left standing for 12 hours under argon atmosphere. The reactionsolution was transferred into a separating funnel, and 600 mL ofdichloromethane was added thereto to dissolve the precipitate. Thesolution was washed with 120 mL of a saturated brine, and then theorganic layer was dried on anhydrous potassium carbonate. The solvent ofthe organic layer obtained by removing potassium carbonate by filtrationwas removed by distillation, and 400 mL of toluene and 80 mL of ethanolwere added to the resulting residue. The flask to which a drying tubewas mounted was heated to 80° C. to completely dissolve the residue.Then, the flask was left standing for 12 hours and slowly cooled down toroom temperature to thereby expedite recrystallization. Depositedcrystal was separated by filtration and dried under vacuum at 60° C.,whereby 13.5 g of N,N-di-(4-biphenylyl)benzylamine was obtained. Asingle neck flask of 300 mL was charged with 1.35 g ofN,N-di-(4-biphenylyl)benzylamine and 135 mg of palladium-activatedcarbon (palladium content: 10% by weight, manufactured by Hiroshima WakoCo., Ltd.), and 100 mL of chloroform and 20 mL of ethanol were added todissolve it. Next, a stirring rod was put in the flask, and then athree-way cock which was equipped with a balloon filled with 2 L ofhydrogen gas was mounted to the flask. The inside of the flask wassubstituted 10 times with hydrogen gas by means of a vacuum pump. Losthydrogen gas was newly filled to set a volume of hydrogen gas again to 2L, and then the solution was vigorously stirred at room temperature.After stirring for 30 hours, 100 mL of dichloromethane was addedthereto, and the catalyst was separated by filtration. Next, thesolution obtained was transferred into a separating funnel and washedwith 50 mL of a sodium hydrogencarbonate saturated aqueous solution, andthen the organic layer was separated and dried on anhydrous potassiumcarbonate. After filtered, the solvent was removed by distillation, and50 mL of toluene was added to the resulting residue to carry outrecrystallization. Deposited crystal was separated by filtration anddried under vacuum at 50° C., whereby 0.99 g of di-4-biphenylylamine wasobtained.

A flask was charged with 10 g of di-4-biphenylylamine, 9.7 g of4,4′-dibromobiphenyl (manufactured by Tokyo Kasei Kogyo Co., Ltd.), 3 gof sodium t-butoxide (manufactured by Hiroshima Wako Co., Ltd.), 0.5 gof bis(triphenylphosphine)-palladium(II) chloride (manufactured by TokyoKasei Kogyo Co., Ltd.) and 500 mL of xylene under argon flow to carryout reaction at 130° C. for 24 hours. After cooling down, 1000 mL ofwater was added thereto, and the mixture was filtered through celite.The filtrate was extracted with toluene, and the extract was dried onanhydrous magnesium sulfate. This was concentrated under reducedpressure, and a crude product obtained was refined through a column andrecrystallized from toluene. It was separated by filtration and thendried, whereby 9.1 g of 4′-bromo-N,N-dibiphenylyl-4-amino-1,1′-biphenyl(Intermediate 21) shown below was obtained.

Shown below are the structures of compounds H1 to H20 which are thearomatic amine derivatives of the present invention produced inSynthetic Practical Examples 1 to 20:

Synthetic Practical Example 1 Synthesis of Compound H1

A flask was charged with 3.4 g of N,N′-diphenylbenzidine, 6.6 g ofIntermediate 4, 2.6 g of sodium t-butoxide (manufactured by HiroshimaWako Co., Ltd.), 92 mg of tris(dibenzylideneacetone)dipalladium(O)(manufactured by Aldrich Co., Ltd.), 42 mg of tri-t-butylphosphine and100 mL of anhydrous toluene under argon flow to carry out reaction at80° C. for 8 hours.

After cooling down, 500 mL of water was added thereto, and the mixturewas filtered through celite. The filtrate was extracted with toluene,and the extract was dried on anhydrous magnesium sulfate. This wasconcentrated under reduced pressure, and a crude product obtained wasrefined through a column and recrystallized from toluene. It wasseparated by filtration and then dried, whereby 4.8 g of a pale yellowpowder was obtained. It was identified as the compound H1 by analysis ofFD-MS (field desorption mass spectrum).

Synthetic Practical Example 2 Synthesis of Compound H2

A flask was charged with 4.1 g of 4,4′-diiodobiphenyl, 8.4 g ofIntermediate 12, 2.6 g of sodium t-butoxide (manufactured by HiroshimaWako Co., Ltd.), 92 mg of tris(dibenzylideneacetone)dipalladium(O)(manufactured by Aldrich Co., Ltd.), 42 mg of tri-t-butylphosphine and100 mL of anhydrous toluene under argon flow to carry out reaction at80° C. for 8 hours.

After cooling down, 500 mL of water was added thereto, and the mixturewas filtered through celite. The filtrate was extracted with toluene,and the extract was dried on anhydrous magnesium sulfate. This wasconcentrated under reduced pressure, and a crude product obtained wasrefined through a column and recrystallized from toluene. It wasseparated by filtration and then dried, whereby 4.8 g of a pale yellowpowder was obtained. It was identified as the compound H2 by analysis ofFD-MS (field desorption mass spectrum).

Synthetic Practical Example 3 Synthesis of Compound H3

Reaction was carried out in the same manner, except that in SyntheticPractical Example 1, 4.4 g of Intermediate 18 was used in place ofN,N′-diphenylbenzidine, whereby 5.1 g of a pale yellow powder wasobtained. It was identified as the compound H3 by analysis of FD-MS.

Synthetic Practical Example 4 Synthesis of Compound H4

Reaction was carried out in the same manner, except that in SyntheticPractical Example 1, 8.1 g of Intermediate 5 was used in place ofIntermediate 4, whereby 5.3 g of a pale yellow powder was obtained. Itwas identified as the compound H4 by analysis of FD-MS.

Synthetic Practical Example 5 Synthesis of Compound H5

A flask was charged with 8.1 g of Intermediate 12, 11.0 g ofIntermediate 21, 2.6 g of sodium t-butoxide (manufactured by HiroshimaWako Co., Ltd.), 92 mg of tris(dibenzylidene-acetone)dipalladium(0)(manufactured by Aldrich Co., Ltd.), 42 mg of tri-t-butylphosphine and100 mL of dehydrated toluene under argon flow to carry out reaction at80° C. for 8 hours.

After cooling down, 500 mL of water was added thereto, and the mixturewas filtered through celite. The filtrate was extracted with toluene,and the extract was dried on anhydrous magnesium sulfate. This wasconcentrated under reduced pressure, and a crude product obtained wasrefined through a column and recrystallized from toluene. It wasseparated by filtration and then dried, whereby 13.1 g of a pale yellowpowder was obtained. It was identified as the compound H5 by analysis ofFD-MS (field desorption mass spectrum).

Synthetic Practical Example 6 Synthesis of Compound H6

Reaction was carried out in the same manner, except that in SyntheticPractical Example 5, 6.5 g of Intermediate 8 was used in place ofIntermediate 12, whereby 7.9 g of a pale yellow powder was obtained. Itwas identified as the compound H6 by analysis of FD-MS.

Synthetic Practical Example 7 Synthesis of Compound H7

Reaction was carried out in the same manner, except that in SyntheticPractical Example 5, 7.5 g of Intermediate 16 was used in place ofIntermediate 12, whereby 7.9 g of a pale yellow powder was obtained. Itwas identified as the compound H7 by analysis of FD-MS.

Synthetic Practical Example 8 Synthesis of Compound H8

Reaction was carried out in the same manner, except that in SyntheticPractical Example 5, 9.7 g of Intermediate 13 was used in place ofIntermediate 12, whereby 10.2 g of a pale yellow powder was obtained. Itwas identified as the compound H8 by analysis of FD-MS.

Synthetic Practical Example 9 Synthesis of Compound H9

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 9.7 g of Intermediate 13 was used in place ofIntermediate 12, whereby 4.3 g of a pale yellow powder was obtained. Itwas identified as the compound H9 by analysis of FD-MS.

Synthetic Practical Example 10 Synthesis of Compound H10

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 7.2 g of Intermediate 9 was used in place ofIntermediate 12, whereby 3.6 g of a pale yellow powder was obtained. Itwas identified as the compound H10 by analysis of FD-MS.

Synthetic Practical Example 11 Synthesis of Compound H12

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 7.2 g of Intermediate 14 was used in place ofIntermediate 12, whereby 5.3 g of a pale yellow powder was obtained. Itwas identified as the compound H12 by analysis of FD-MS.

Synthetic Practical Example 12 Synthesis of Compound H14

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 4.8 g of Intermediate 2 was used in place of4,4′-diiodobiphenyl and that 6.5 g of Intermediate 8 was used in placeof Intermediate 12, whereby 3.9 g of a pale yellow powder was obtained.It was identified as the compound H14 by analysis of FD-MS.

Synthetic Practical Example 13 Synthesis of Compound H15

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 3.3 g of 1,4-diiodobenzene was used in place of4,4′-diiodobiphenyl and that 6.5 g of Intermediate 8 was used in placeof Intermediate 12, whereby 3.3 g of a pale yellow powder was obtained.It was identified as the compound H15 by analysis of FD-MS.

Synthetic Practical Example 14 Synthesis of Compound H16

Reaction was carried out in the same manner, except that in SyntheticPractical Example 1, 2.5 g of Intermediate 11 was used in place ofN,N′-diphenylbenzidine and that 8.0 g of Intermediate 19 was used inplace of Intermediate 4, whereby 2.1 g of a pale yellow powder wasobtained. It was identified as the compound H16 by analysis of FD-MS.

Synthetic Practical Example 15 Synthesis of Compound H17

Reaction was carried out in the same manner, except that in SyntheticPractical Example 1, 6.5 g of Intermediate 17 was used in place ofN,N′-diphenylbenzidine and that 8.0 g of Intermediate 19 was used inplace of Intermediate 4, whereby 7.1 g of a pale yellow powder wasobtained. It was identified as the compound H17 by analysis of FD-MS.

Synthetic Practical Example 16 Synthesis of Compound H18

Reaction was carried out in the same manner, except that in SyntheticPractical Example 1, 6.5 g of Intermediate 17 was used in place ofN,N′-diphenylbenzidine and that 6.5 g of Intermediate 20 was used inplace of Intermediate 4, whereby 5.9 g of a pale yellow powder wasobtained. It was identified as the compound H18 by analysis of FD-MS.

Synthetic Practical Example 17 Synthesis of Compound H19

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 3.5 g of 2,7-dibromo-9,9-dimethylfluorene was usedin place of 4,4′-diiodobiphenyl and that 6.5 g of Intermediate 8 wasused in place of Intermediate 12, whereby 3.7 g of a pale yellow powderwas obtained. It was identified as the compound H19 by analysis ofFD-MS.

Synthetic Practical Example 18 Synthesis of Compound H20

Reaction was carried out in the same manner, except that in SyntheticPractical Example 2, 4.8 g of tris(4-bromophenyl)amine was used in placeof 4,4′-diiodobiphenyl and that 9.7 g of Intermediate 8 was used inplace of Intermediate 12, whereby 4.8 g of a pale yellow powder wasobtained. It was identified as the compound H20 by analysis of FD-MS.

Example 1 Production of Organic EL Device

A glass substrate (manufactured by Geomatech Co., Ltd.) of 25 mm×75mm×1.1 mm thickness equipped with an ITO transparent electrode wassubjected to supersonic wave washing in isopropyl alcohol for 5 minutesand then to UV ozone washing for 30 minutes.

After washed, the glass substrate equipped with a transparent electrodeline was loaded in a substrate holder of a vacuum vapor depositionapparatus, and a film of the compound H1 described above having a filmthickness of 60 nm was formed on a face of a side at which thetransparent electrode line was formed so that it covered the transparentelectrode described above. This H1 film functions as a hole injectinglayer. A film of a compound TBDB shown below having a film thickness of20 nm was formed on the above H1 film. This film functions as a holetransporting layer. Further, a compound EM1 shown below was depositedthereon to form a film having a film thickness of 40 nm. At the sametime, the following amine compound D1 having a styryl group wasdeposited as a light emitting molecule so that a weight ratio of EM1 toD1 was 40:2. This film functions as a light emitting layer.

A film of Alq shown below having a film thickness of 10 nm was formed onthe above film. This film functions as an electron injecting layer.Then, Li (Li source: manufactured by Saesgetter Co., Ltd.) which was areducing dopant and Alq were subjected to binary vapor deposition toform an Alq:Li film (film thickness: 10 nm) as an electron injectinglayer (cathode). Metal Al was deposited on the above Alq:Li film to forma metal cathode, whereby an organic EL device was formed.

Further, a current efficiency of the organic EL device thus obtained wasmeasured, and a light emitting color thereof was observed. The luminancewas measured by means of CS1000 manufactured by Konica Minolta Co., Ltd.to calculate the current efficiency at 10 mA/cm². Further, the halflifetime thereof in light emission was measured at an initial luminanceof 5000 cd/m² and room temperature in operating at a DC constantelectric current, and the results thereof are shown in Table 1.

Examples 2 to 12 Production of Organic EL Devices

Organic EL devices were prepared in the same manner, except that inExample 1, compounds described in Table 1 were used as hole transportingmaterials in place of the compound H1.

The current efficiencies of the organic EL devices thus obtained weremeasured, and the light emitting colors thereof were observed. Further,the half lifetimes thereof in light emission were measured at an initialluminance of 5000 cd/m² and room temperature in operating at a DCconstant electric current, and the results thereof are shown in Table 1.

Comparatives Examples 1 to 7

Organic EL devices were prepared in the same manner, except that inExample 1, a comparative compound 1 to a comparative compound 7 wereused as a hole transporting material in place of the compound H1.

The current efficiencies of the organic EL devices thus obtained weremeasured, and the light emitting colors thereof were observed. Further,the half lifetimes thereof in light emission were measured at an initialluminance of 5000 cd/m² and room temperature in operating at a DCconstant electric current, and the results thereof are shown in Table 1.

Example 13 Production of Organic EL Device

An organic EL device was prepared in the same manner, except that inExample 1, the following arylamine compound D2 was used in place of theamine compound D1 having a styryl group. Me is methyl.

A current efficiency of the organic EL device thus obtained wasmeasured, and a light emitting color thereof was observed. Further, thehalf lifetime thereof in light emission was measured at an initialluminance of 5000 cd/m² and room temperature in operating at a DCconstant electric current, and the results thereof are shown in Table 1.

Comparatives Example 8

An organic EL device was prepared in the same manner, except that inExample 13, the comparative compound 1 described above was used as ahole transporting material in place of the compound H1.

A current efficiency of the organic EL device thus obtained wasmeasured, and a light emitting color thereof was observed. Further, thehalf lifetime thereof in light emission was measured at an initialluminance of 5000 cd/m² and room temperature in operating at a DCconstant electric current, and the results thereof are shown in Table 1.

Example 14 Production of Organic EL Device

An organic EL device was prepared in the same manner, except that inExample 1, an acceptor compound shown below was used to form a film of10 nm between the anode and the compound H1 described above and that afilm thickness of the compound H1 described above was changed to 50 nm.

A current efficiency of the organic EL device thus obtained wasmeasured, and a light emitting color thereof was observed. Further, thehalf lifetime thereof in light emission was measured at an initialluminance of 5000 cd/m² and room temperature in operating at a DCconstant electric current, and the results thereof are shown in Table 1.

Comparatives Example 9

An organic EL device was prepared in the same manner, except that inExample 14, the comparative compound 1 described above was used as ahole transporting material in place of the compound H1.

A current efficiency of the organic EL device thus obtained wasmeasured, and a light emitting color thereof was observed. Further, thehalf lifetime thereof in light emission was measured at an initialluminance of 5000 cd/m² and room temperature in operating at a DCconstant electric current, and the results thereof are shown in Table 1.

TABLE 1 Hole Light transporting Voltage emitting Half lifetime material(V) color (hour) Example 1 H1 6.0 blue 440 Example 2 H2 6.2 blue 420Example 3 H3 6.3 blue 370 Example 4 H5 6.4 blue 410 Example 5 H6 6.4blue 400 Example 6 H7 6.3 blue 420 Example 7 H8 6.2 blue 380 Example 8H12 6.4 blue 330 Example 9 H16 6.2 blue 420 Example 10 H14 6.1 blue 430Example 11 H15 6.5 blue 440 Example 12 H19 6.3 blue 420 Example 13 H16.1 blue 430 Example 14 H1 5.7 blue 340 Comparative Comparative 7.1 blue280 Example 1 compound 1 Comparative Comparative 6.6 blue 80 Example 2compound 2 Comparative Comparative 6.2 blue 110 Example 3 compound 3Comparative Comparative 6.4 blue 200 Example 4 compound 4 ComparativeComparative 6.6 blue 150 Example 5 compound 5 Comparative Comparative6.8 blue 260 Example 6 compound 6 Comparative Comparative 6.9 blue 240Example 7 compound 7 Comparative Comparative 7.0 blue 270 Example 8compound 1 Comparative Comparative 6.5 blue 130 Example 9 compound 1

A rise in the voltage (ΔV=(voltage after 200 hours)−(initial voltage))in 200 hours after measuring the lifetime was confirmed in therespective cases of the compound H1, the compound H12 and thecomparative compound 4 to find that it was 0.2 V in the case of thecompound H1, 0.4 V in the case of the compound H14 and 0.7 V in the caseof the comparative compound 4. It is considered that the electricallymore unstable the compound is, the larger the rise in voltage is.

INDUSTRIAL APPLICABILITY

As explained above in details, the aromatic amine derivative of thepresent invention reduces the driving voltage and makes the moleculesless liable to be crystallized, and addition thereof to the organic thinfilm layer makes it possible to enhance a yield in producing the organicEL device and materialize the organic EL device having a long lifetime.

What is claimed is:
 1. An aromatic amine compound represented by thefollowing Formula (1):

wherein L₁ represents a divalent group selected from the groupconsisting of phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl,9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl,9-phenanthryl, 1-naphthacenyl, 2-naphthacenyl, 9-naphthacenyl,1-pyrenyl, 2-pyrenyl, 4-pyrenyl, 2-biphenylyl, 3-biphenylyl,4-biphenylyl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl,m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl,p-tolyl, p-t-butylphenyl, p-(2-phenylpropyl)phenyl, 3-methyl-2-naphthyl,4-methyl-1-naphthyl, 4-methyl-1-anthryl, 4′-methylbiphenylyl,4″-t-butyl-p-terphenyl-4-yl, fluoranthenyl, fluorenyl and9,9-dimethylfluorenyl; at least one of Ar₁ to Ar₄ is represented by thefollowing Formula (2):

wherein R₁ is an aryl group having 6 to 50 ring atoms or a cyano group,a is an integer of 1 to 3, and L₂ represents a divalent group selectedfrom the group consisting of phenyl, 1-naphthyl, 2-naphthyl,2-biphenylyl, 3-biphenylyl, 4-biphenylyl, o-tolyl, m-tolyl, p-tolyl,fluoranthenyl, fluorenyl, and 9,9-dimethylfluorenyl; in Formula (1),among Ar₁ to Ar₄, the groups which are not represented by Formula (2)each are independently an aryl group having 6 to 50 ring atoms;substituents for Ar₁ to Ar₄ each are independently an aryl group having6 to 50 ring atoms, a branched or linear alkyl group having 1 to 50carbon atoms, a halogen atom, or a cyano group; and when a=2, two R₁ donot form a benzothiophenyl group.
 2. The aromatic amine compound asdescribed in claim 1, wherein Formula (2) is represented by thefollowing Formula (3):

wherein R₁ is an aryl group having 6 to 50 ring atoms.
 3. The aromaticamine compound as described in claim 1, wherein in Formula (1), Ar₁ isrepresented by Formula (2).
 4. The aromatic amine compound as describedin claim 1, wherein in Formula (1), Ar₁ and Ar_(e) are eachindependently represented by Formula (2).
 5. The aromatic amine compoundas described in claim 1, wherein in Formula (1), Ar₁ and Ar_(a) are eachindependently represented by Formula (2).
 6. The aromatic amine compoundas described in claim 1, wherein in Formula (1), three or more of Ar₁ toAr₄ are different from each other, and the aromatic amine compound isasymmetric.
 7. The aromatic amine compound as described in claim 1,wherein in Formula (1), three of Ar₁ to Ar₄ are the same, and thearomatic amine compound is asymmetric.
 8. The aromatic amine compound asdescribed in claim 1, wherein in Formula (1), among Ar₁ to Ar₄, thegroups which are not represented by Formula (2) each are independentlyphenyl, biphenylyl, terphenylyl or fluorenyl.
 9. The aromatic aminecompound as described in claim 1, wherein in Formula (1), L₁ isbiphenylylene, terphenylylene or fluorenylene.
 10. The aromatic aminecompound as described in claim 1, wherein in Formula (2), L₂ isphenylene, biphenylylene or fluorenylene.
 11. The aromatic aminecompound as described in claim 1, wherein in Formula (2), R₁ is phenyl,naphthyl or phenanthrene.
 12. The aromatic amine compound as describedin claim 1, wherein: in Formula (1), among Ar₁ to Ar₄, the groups whichare not represented by Formula (2) each are independently phenyl,biphenylyl, terphenylyl, or fluorenyl, and L₁ is biphenylylene,terphenylylene or fluorenylene; and in Formula (2), L₂ is phenylene,biphenylylene or fluorenylene.
 13. An organic electroluminescence devicecomprising an organic thin film layer comprising a single layer or aplurality of layers comprising at least one light emitting layer,wherein: the organic thin film layer is interposed between a cathode andan anode; and at least one layer in the organic thin film layercomprises the aromatic amine compound of claim 1 as a single componentor a mixed component.
 14. The organic electroluminescence device asdescribed in claim 13, wherein: the organic thin film layer comprises ahole transporting layer; and the hole transporting layer comprises thearomatic amine compound.
 15. The organic electroluminescence device asdescribed in claim 13, wherein: the organic thin film layer comprises aplurality of hole transporting layers; and the hole transporting layernot in direct contact with the light emitting layer comprises thearomatic amine compound.
 16. The organic electroluminescence device asdescribed in claim 13, wherein: the organic thin film layer comprises ahole injecting layer; and the hole injecting layer comprises thearomatic amine compound.
 17. The organic electroluminescence device asdescribed in claim 13, wherein the hole injecting layer comprises thearomatic amine compound as a main component.
 18. The organicelectroluminescence device as described in claim 13, wherein the lightemitting layer comprises a styrylamine compound and/or an arylaminecompound.
 19. The organic electroluminescence device as described inclaim 13, wherein, among respective layers constituting the holeinjecting layer and the hole transporting layer, a layer in contact withthe anode comprises an acceptor material.
 20. The organicelectroluminescence device as described in claim 13, wherein the organicelectroluminescence device emits light of a blue color.